JPH02545A - Device for formation of image - Google Patents

Abstract

PURPOSE:To easily cope with the alteration of a sheet size at a host side by outputting a video clock signal in which the number of output pulses is varied in response to the size from a printing side, and feeding a video data signal from the host side to the printing side on the basis of the clock signal. CONSTITUTION:A host system 500 feeds video data signals IVDAT1, IVDAT2 of dot image data to an interface circuit 519 on the bias of its video clock signal, etc. Thus, even if the system 500 does not calculate to alter the number of pulses and its feeding timing of the data signal so as to change the print starting position of a sheet by a 2-color LBP 199, the data signal is synchronized with the clock signal from the LBP corresponding to the sheet size and fed from the system 500 to the LBP 199. Accordingly, an increase in the program capacity in the system 500 can be suppressed, and a waiting time in case of starting a printing operation can be rapidly suppressed to a short value.

Description

[Detailed description of the invention]

[Object of the Invention] (Industrial Application Field) The present invention provides an image forming device suitable for a printing device such as a laser printer that includes a step of scanning a laser beam to form an electrostatic latent image on a photoreceptor. Regarding. (Prior Art) In the case of this type of conventional image forming apparatus, as shown in FIG. 25, for example, the printing side 1 is constituted by a printer 2, and the host side 3 is constituted by a controller 4. Then, by sending a status signal from the printer 2 to the controller 4 and sending a command from the controller 4 to the printer 2, the system status can be checked based on the system status. This command is sent to control the printer 2. Further, when controlling the printer 2, the printer 2 outputs a horizontal synchronization signal to the controller 4, and the controller 4 sends out a video data signal to the printer 2 based on the horizontal synchronization signal. However, when sending the video data signal from the controller 6 of the host side 5 to the printing side 1, the video data signal was sent based only on the horizontal synchronization signal output from CIJJ[1. Every time the paper size is changed on the printing side 1, the number of pulses and sending timing of the T' video data signal on the host side 3 must be changed as appropriate. <Problems to be Solved by the Invention> In other words, in the case of conventional image forming apparatuses, when the paper size is changed on the printing side, the printing start position on the paper is changed in response to this change. The number of pulses of the video data signal and its transmission timing were changed as appropriate on the host side. As a result, on the host side, the /program capacity 1 increases significantly due to the process of changing the number of pulses of the video data signal and its sending timing, and as a result, the waiting time when starting the printing operation increases, etc. There was a rare problem that affected the processing speed. The present invention has been made in view of the above problems, and its purpose is to
On the host side, it is an object of the present invention to provide an image forming apparatus that can easily accommodate changes in the paper size. [Structure 1 of the Invention (Means for Solving the Problems) In order to achieve the above-mentioned object-4, the present invention is composed of a printing side and a host side that sends various data signals to the printing side, The present invention is characterized in that a video clock signal whose output pulse number changes depending on the paper size is output from the printing side, and a video data signal is sent from the host side to the printing side based on this video clock signal. (Function) With this configuration, each time there is a change in paper size on the printing side, the number of output pulses changes depending on the paper size.

[Since the video data signal is sent from the host side to the printing side based on the cock signal, it is difficult to obtain the number of pulses of the host glAC video data signal and its sending timing in order to change the printing start position on paper. becomes unnecessary. Therefore, it is possible to suppress an increase in the program capacity on the host side, and accordingly, it is possible to suppress the downtime when starting a printing operation as much as possible. (Embodiment) FIG. 1 is a block diagram schematically showing an embodiment of an image forming apparatus to which the present invention is applied. The image forming apparatus of this embodiment has two colors L constituting the printing side.
The B P 199 and the host system 500 (external devices such as electronic computers and word processors) are coupled via a transmission controller (interface circuit, etc.) not shown. Then, the two-color LBP 199 receives two types of dot image data from the host system 500, modulates each of the two laser beams, executes writing on the photoreceptor (image carrier), and writes the two types of dot image data written on the photoreceptor (image carrier). Kind of dot
Each image data is independently developed and transferred onto recording paper. That is, this two-color laser beam printer (LaserB
eat P r+nter, below 2 colors 1- B P
4) At 199, the peripheral portion of the photoreceptor 200 is first charged! 201. Table 1 part activity sensor 202. First developer 2
03. Second charger 204. Second surface upper sensor 205.
Second phenomenon device 206. Pre-transfer charger 2076 Transfer charger 2
08. A stripping charger 209, a cleaner 210, and a static eliminator 211 are provided, and a second laser beam 3 is connected between the first surface potential sensor 202 and the first charger 203.
10 is irradiated onto the photoreceptor 200 to perform a first exposure, and a second laser beam 310 is irradiated between the second surface layer position sensor 205 and the second developer 206 to perform a second exposure. being done. Further, the υ1611 portion of the two-color LBP in this embodiment has a block configuration as shown in FIG. This two-color L B P O) all 1111 part c, with the CPU 501 as the il + 11 sin center, the ROM 502 in which the system program is stored, the ROM 503 in which the data table is stored, the 6 RAM 504 used as working memory, and the ter 1"? -505 and I
/ 07'-Evening input/output device 506, print data writing IIIt[1 circuit 513, interface circuit 5
Basically, it is equipped with 19. The contents of the data table stored in the ROM 503 are as shown in FIG.
contains first color top margin control data and address (4
002) and (4003) contain second color top margin control data, and addresses (4004) and (4005) contain left margin $It2j data. Addresses (4006) and (4007) contain bottom margin control data for paper size A3, and address (400
8) (4009) contains data for controlling the light margin of the same paper size. Below, tables corresponding to various paper sizes are similarly included up to the address (4083). From address (4090) is data for top margin coarse adjustment, from address (4080) is data for top margin fine adjustment, from address (4000) is data for left margin coarse adjustment, from address (4100) is data for left margin fine adjustment. Data and address (4120) contain two-beam scanning length correction data, which correspond to switches 1 to n, respectively. These margin control data, coarse adjustment data, and fine adjustment data are used as set data for a margin control counter and a binary counter of a print data write control circuit 513, which will be described later. Address (6000) (6001) contains first phenomenon bias data for red toner, address (6002) (6001).
003) contains second developing bias data. Below is the first toner: front toner, edge toner and black toner. The second developing bias data similarly contains addresses (up to 600F3) and is used as set data for phenomenon bias control of the process control circuit 522, which will be described later.Addresses (6100) (6101) contain the first charging potential control Contains target surface potential table data, 25°
This is the reference value for C. Addresses (6102) and (6103) contain error table data at the time of convergence, and represent the allowable control range for the target surface potential. Addresses (6104) and (6105) contain initial control output table data, which is the set value of the first electrification charger that is output at the beginning during warming up. Addresses (6106) and (6107) contain minimum correction table data. Address (6108) (6109) has surface potential limit table data, address (610A>(610B>) has control output upper limit table data, address (610G) (
6100) contains control output lower limit table data, and the surface potential limit table data, the control output upper limit table data, and the control output lower limit table data are used for self-diagnosis of the fblJ system. Below, the table corresponding to the second charging potential control similarly contains up to address (611B>. Address (6120
) contains charging potential temperature correction table data in a temperature range of 10'C to 40''C, which serves as temperature correction data for the target surface potential table data of 25°C. Timer 505 is a general-purpose timer; Generates basic timing signals for controlling paper transport, photoconductor processing, etc. The input/output device 506 outputs display data to the operation display section 507, inputs various switch data, etc., and controls each detector 508 in the control section. Input, motor. Output to drive circuit 509 that drives drive elements 510 such as clutches and solenoids, output to drive circuit 511 that drives laser scan motor 512 for scanning two laser beams, potential sensor, temperature. Input/output is performed for a process control circuit 522 that controls the output of a high voltage power supply, 523, etc. in response to input of a detection signal from a sensor, etc. A print data write control circuit 513 is for writing image data of the first color. drive control of a second laser modulation circuit 514 that performs optical modulation of the first semiconductor laser 302 and a second laser modulation circuit 521 that performs optical modulation of the second semiconductor laser 303 for including image data 1 of the second color. Then, the print data of the video image transferred from the host system 500 is controlled to be placed at a predetermined position on the photoreceptor.At this time, the beam detector 518, which uses a high-speed response PIN diode, One of the two light beams being scanned by the scan motor is detected, and the beam detection circuit 517 detects the beam detector 5.
The analog signal from 18 is digitized by a high-speed converter to create a horizontal synchronizing pulse, which is sent to the control circuit 513 including print data 8. The interface circuit 519 connects the host system 500
It outputs status data to the post system 500 and receives command data and print data from the post system 500. Further, a power supply device 520 is provided to supply power to each part of the control section. The details of one important block in FIG. 2 will be explained below. FIG. 4 is a diagram showing details of the interface signals between the interface circuit 519 and the host system 500 in FIG. 2. In the figure, D7-DO is an 8-bit bidirectional data bus, [08TA is the data bus selection signal, and indicates whether it is used as a status data bus to the host system 500 or as a command data bus from the host system 500. Choose which one to use. l5
TB is a strobe signal for latching the above command data in the interface circuit, and 188Y is a signal for permitting transmission of the strobe signal 15TB and for permitting reading of status data. IH8YNI is the first color horizontally! The vl signal requests transmission of one line of print data. IVCLKl is a video clock signal for the first color and requests transmission of one dot of print data. IPENDI is the page end signal of the first color and notifies the end of the line. The host system 500 is the IH3YN1.1VCL.
Based on KI, the video data signal IVDAT1 of the first color dot image data is sent out, and when IPENDI is received, the sending is stopped. Similarly, I) (SYN2 is the second color horizontal synchronization signal, IV
CLK2 is the second color video clock signal, I PEN
D2 is a page end signal for the second color, and the host system 500 generates the video data signal I of the dot image data for the second color based on the IH3YN2 and IVCLK2.
Sends VDAT2 and stops sending when IPEND2 is received. This video data signal IVDATI, IV
D A T 2 C is sent to the print data write control circuit. The above relationship is shown in Figure 5. IPRDY is a signal that informs that the two-color LBPI 99 is ready, [PREQ is a signal that allows the sending of the print start signal IPRNT from the host system 500, and IPRME is a signal that sets the two-color LBPI 99 to the initial state. Prime signal, IPOW is two-color LBPI 99
A signal that informs you that the power is on. Next, details of the commands and statuses used in the two-color L B P 199'c are shown in FIGS. 6 and 7, respectively. In FIG. 6, SR1 to SR7 are status request commands corresponding to statuses 1 to 7 in FIG.
is the cassette upper stage paper feed specification command, C3TL is also the lower stage specification command, VSYNC is the host system 5.0
Command that specifies the start of sending print data from 0, SP
l, SP2. DPl is a command that specifies the print mode; SPl is a mode that specifies printing operation for only the first color, SP2 is a printing operation for only second color, and DPl is a mode that specifies printing operation for both the first color and second color. . MF1 to MF9 indicate manual feed mode designation commands, respectively. In FIG. 7, during paper transport, paper is being fed 2
A status indicating that paper is being transported in the color LBP 199. A VSYNC request is a status indicating that the two-color LBP 199 has received a command to start printing and is now ready to receive print data. For manual feed, the paper feed mode is set. The status indicates that the cassette is in manual feed mode, the upper/lower cassette indicates the status of the selected cassette in the cassette paper feeding mode, the print mode is 1st color, 2nd color, 2
The color is the status indicating the selected print mode,
The cassette size (upper row) and the cassette size (lower row) are the statuses that indicate the size code of the cassette installed in the device, and the toner color (first color) and toner color (second color) are the current f! The status indicates the toner color code of the JI device, the status indicates that test/maintenance is in test/maintenance state C, the data resend request indicates that reprinting is required due to a jam, etc.
During wait, the status indicates that the two-color LBP is in a warm-up state of constant 15, and the operator call indicates that an operator call factor of status 5 has occurred. Serviceman call indicates that a serviceman call factor of status 6 has occurred. Toner bag replacement indicates that the toner pack is full of toner. Paper Out indicates that there is no paper in the specified cassette, Paper Jam indicates that paper has jammed inside the machine. No toner of the first color indicates that there is no toner in the first developing device.No toner of the second color indicates that there is no toner in the second developing device. The second laser failure indicates that the laser diode does not reach the specified output, or the beam detector cannot detect the beam.The scan motor failure indicates that the scan motor fails. The first potential sensor failure and the second potential sensor failure indicate that the specified number of rotations has not been reached even after a certain period of time has elapsed, or that the number of rotations has deviated from the specified number of rotations for some reason after the specified number of rotations. The number of sheets to be retransmitted is determined by the number of sheets required to be reprinted when the data retransmission request status occurs. 8 is a detailed circuit diagram of the first semiconductor laser 302, the second laser modulation circuit 521, and the second semiconductor laser 303. First, the first laser modulation circuit 514 and the first semiconductor laser 302 will be explained. , 302 is a first semiconductor laser diode, which is composed of a laser diode 812a that emits light;
It consists of a monitoring photodiode 811a that monitors the output beam intensity from the laser diode. 8098G (a high-frequency transistor performs optical modulation of the first loser diode 812a. Resistor R29a is a current detection resistor, 810a is a transistor for flowing a bias current to the second loser diode 812a, and R30a is its current limiting resistor. R27a is a base current limiting resistor of the transistor 810a, and 817a is an inverter.The input of the inverter 81a is a losser diode enable signal L.
DONIO is input, and when this signal becomes LOW level, the transistor 810a becomes ONL,...
A bias current flows through the first loser diode 812a. 807a and 808a are high-speed analog switches for modulating the losser diode 812a, and when a HIGH level voltage is applied to the gate (G) of each analog switch, the connection between the drain (D) and the source (S) becomes high. The resistance becomes low and turns ON. When a LOW level voltage is applied to the gate (G), the resistance becomes high and turns off. R21a is analog switch 8078.808a
Short-circuit protection resistance when ON-FF changes, 813a, 8
14a is a gate driver for the analog switches 807a and 808a. GO2a and C03a are speed-up capacitors, and R2, 4a, and R25a are input resistances of the gate drivers 813a and 814a. 815a, 816a G, tEXCLUSIVE-
ORG1~ changes depending on the output of the 2AND gate 820a. The 2AND gate 820a outputs LOW when either of the two gate inputs becomes LOW level.
Wt/Berni, the output of the EXCLUSIVE-OR gate 815a becomes LOW level, the analog switch 807a is turned ON, and the LOZER diode 8 is turned on.
12a is in the ON state. The condition that the output of the AND gate 820a becomes LOW level is that the first video data signal @ r VDAT10SL
OW level or 1st sample f4 SAMPI
This is when O is at the LOW level. When the inputs of the 2AND gate are both HIG)-level, the EXCLU
The output of the SIVE-OR gate 816a becomes L and OW level, turning on the analog switch 808a and turning off the loser diode 812a. The 806a+ is an operational amplifier and constitutes a voltage follower circuit. DOI is a Zener diode that regulates the output of the first loser diode 812a to be within the rated value. Further, the resistors R19a and C01a constitute an integrating circuit, and R20a is a discharge resistor that discharges one load of the capacitor C01a at a constant rate of 91°. 8
04a is an analog switch whose gate (G) is connected to an inverter 805a, and the first sample signal SAMPIO is input to the input of the inverter 805a. 8
03a is a transistor for level conversion, R22a is a base current limiting resistor of the transistor 803a, and R18a is a current limiting resistor when charging the capacitor C01a. 802ai], and this comparator has a hysteresis characteristic due to the action of resistors R14a and R15a. The resistor R14 is connected to the input side of the comparator 802a.
The output voltage of the first router monitor multiplier 801a is applied through a. 5oia is the first loser diode 812
This is an amplifier for the output of the photodiode 811a that detects the optical output from the photodiode 811a. Resistance J4R12a, R13a, VR
O1a is a resistor that regulates the degree of increase in RIJ of the operational amplifier 801a. Therefore, by changing VROla, the amplifier of operational amplifier 801a can be changed. R11a is a load resistor C for the output of the photodiode in the first loser diode, and a voltage proportional to the output current of the photodiode 811a is obtained across both ends of this resistor R11a. Since the output current of the photodiode 811a is proportional to the optical output of the laser diode 812a, the optical output of the laser diode 812a can be adjusted by varying the volume VRO1a. 818a is a comparator that checks whether the 1st loser diode is emitting light, and 818a is connected to the negative input. tIi
The output voltage of the operational amplifier 801a described in IJ is applied. Further, a voltage divided by resistors R16a and R17a is applied to the + side input. Therefore, when the first loser diode 812a emits light and its output becomes equal to or higher than the M voltage divided by the resistors R16a and R17a, the output level of the inverter 818a changes from the HIGH level to the LOW level, and the second -The ready signal LR[)YlO is output. Further, a laser light ω setting voltage is applied to one input terminal of the comparator 802a. As the set voltage, the output of the Portischiff 40W 819 is applied. The exposure adjustment volume 8 is connected to the input terminal of the voltage follower 819.
21 and resistor R31 is input, and by varying the exposure adjustment volume 821, the output voltage of the voltage follower 819 is also changed. Next, the first loser modulation circuit 514 and the second loser diode 30
Explain the operation of step 2. First, when the first loser diode enable signal LDONIO becomes LOW level, a bias current flows through the first loser diode 812a. Next, the first
When the sample signal SAMP10 reaches the OW level, the analog switches 804a and 807a are turned on, but since the capacitor C01a is not charged, the output of the voltage follower 806a is Ov, and the modulation transistor 809a is not ONL. Therefore, the first rule
A current flows through the diode 812a to such an extent that it does not emit light. At this time, since no current flows through the first photodiode 8118, the output of the comparator 802a is L.
Since the voltage becomes OW level and the transistor 803a is turned off, the capacitor C01a is charged through the resistors R18a and R19a. The time constants of the resistors R18a, R19a and capacitor C01a used for this charging are selected to be about 20 to 50 Ilsec. If this value is very small, the response of the stabilization circuit will be too fast,
Fluctuations in the laser light output level become large. If it is too large, the responsiveness will deteriorate and it will take time to stabilize the optical output. By charging the capacitor C01a, the output voltage of the voltage follower 806a also gradually increases. Therefore, as the base voltage of the laser modulation transistor 809a increases, a current flows to the collector. The transistor 81 is connected to the first loser diode 812a.
A summation current of the bias current from 0a and the collector current from the true transistor 809a flows, and when the summation current exceeds the threshold current of the first loser diode 812a, the second loser diode 812a emits light. When the first loser diode 812a emits light, a current flows through the first monitoring photodiode 811a, and the input terminal voltage of the operational amplifier 801A increases, and its output voltage also increases to a value equal to the input voltage. Output. When the output voltage of the operational amplifier 801A becomes equal to or higher than the voltage divided by the resistors R16a and R17a, the output of the comparator 818a, that is, the first loser ready signal LRDY10 changes from HIGH to LOW level. When the output voltage of the operational amplifier 801A becomes higher than the voltage at one input terminal of the comparator 802a, that is, the set voltage for the router optical waveguide, the output of the comparator 802a changes from LOW to HIGH level.
Transistor 803a turns on, and capacitor C01
a is discharged through resistor R19a. Therefore, the base voltage of the modulation transistor 809a also decreases, and the optical output of the first loser diode decreases. When the optical output of the first loser diode decreases, the comparator 802a
The voltage at the input terminal of 10 is also less than the set voltage of the 1st loser light,
The transistor 803a is turned off again, and the resistor R18a is connected to the capacitor C01a again. It is charged up through R19a. In this way, when the optical output of the first loser diode 812a reaches the final set voltage for the direction of the loser light, the comparator 802a gradually repeats ON-OFF at around the best set voltage for the first loser light. The optical output of the first loser diode 812a is stabilized. When the CPU 501 confirms that the loser ready signal LRDY10 has become a LOW level via the I10 port, it starts the operation of a sample timer, which will be described later, and outputs the first sample signal every line outside the printing area. S.A.
MPIO is set to LOW level for a certain period of time, and the analog switch 804a is turned on. 807a is turned on to stabilize the laser beam characteristics. Next, when the two-color LBP 99 becomes ready for printing and the first video data signal VDAT10 is sent from the host system 500, the first video data signal VDATI
The analog switches 807a and 808a alternately turn on and off in response to
The laser diode 812a is modulated by the laser diode 9a to write dot image data on the photoreceptor 200. The second laser modulation circuit 514 and the first semiconductor laser 30
2 has been described in detail, the second laser modulation circuit 521
The second semiconductor laser 303 also has a similar configuration, but the second semiconductor laser 303 has a similar configuration.
The output of the voltage follower 819 is applied to the optical setting voltage of the laser diode 812b, that is, the input terminal of the comparator 802bk. Therefore, by varying the exposure adjustment volume 821, the output voltage of the voltage follower 819 also changes, so the comparator 80
One input terminal voltage of 2a and 802b changes simultaneously. Therefore, the light output of the first laser diode 812a and the light output of the second laser diode 812b are adjusted to the exposure volume 821.
can be adjusted at the same time by making them variable. FIG. 9 is a detailed circuit diagram of the beam detector 517 and beam detector 518 in FIG. 2. In Figure 9, 5
18 is a beam detector that uses a PIN diode with very fast response. Furthermore, this beam detector 518 serves as a reference pulse when writing print data onto the photoreceptor 200, and the generation position of this pulse must always be stable. The anode side of the beam detector 518 is connected to one input terminal of a high speed comparator 825 through a load resistor R41 and a resistor R44. Also, high-speed comparator 825 ÷
A voltage divided by resistors R42 and R43 is applied to the dynamic input terminal through R45. Further, a capacitor C10 for noise removal is connected in parallel to the resistor R43. Further, R46 is a positive feedback resistor for providing hysteresis characteristics, and C11 is a feedback capacitor for applying feedback at high speed to improve the output waveform. Next, the operation will be explained. When the laser beam passes over the beam detector 518 at high speed, a pulse current flows to the beam detector 518, and one side input ψ of the comparator 825 is
: A positive pulse voltage is generated. This pulse voltage is compared with the positive input terminal voltage of the comparator 825, and a negative pulse H8YO is outputted from the output of the comparator 825. FIG. 10 is a diagram showing a one-time scan range of the laser beam on the photoreceptor 200 and the positional relationship of beam detection positions, data writing positions, etc. within the range. In FIG. 10, 900 is the beam scanning start point, 901 is the beam scanning end point, and the beam that has reached the beam scanning end point 901 is moved by the next surface of the polygon mirror for a time of O'c.
The next beam is started from the inter-beam starting point 900. 902
indicates the beam detection starting point of the beam detector 518, and 90
3 indicates the left end surface of the photoreceptor, and 910 similarly indicates the right end surface. 904 represents the left end surface of the paper, 909 represents the 6th end surface of the paper size Δ3, and 907 represents the right end surface of the paper size 86. 905 is the data insertion start point, 908 is the paper size A3
The data wrapping end point of 90G represents the data wrapping end point of paper size A6. d2 is the distance from the frame detection point 902 to the writing start point,
d3 is A6'j - is B included Distance to end point d4 is A3
Each represents the distance to the end point including size 3. Also d
, l, t represent the range of one scan of the beam. d5. d indicates the effective printing range in 86 and A3, respectively. As can be seen from this drawing, the paper in this printer is always fed based on the left end surface of the paper, and the printing start point 905 from the target beam detection device 902 is the same for each paper size. Therefore, the C beam detection 3518 detects the beam, and after a time corresponding to the distance from C to the writing start point, the data may be updated. FIG. 11 shows the paper size and print area portion of FIG. 10 not only in the horizontal direction but also in the entire paper. In FIG. 11, 917 represents A6 paper and 918 represents A3 paper. 904,905,906°907.90
8,909 shows the same position as in FIG. 911 is the leading edge of the paper, 913 is the f-evening start point in the vertical direction of the paper, 912 is the trailing edge of the A3 size paper, 916 is the A
Represents the end point of 3 sizes of data. Reference numeral 915 represents the trailing edge of the paper for size 6, and 914 represents the end point of wrapping data for size 6. Fig. 12 shows the printing decoding control circuit 5 in Fig. 2.
13 is a detailed circuit diagram. This print data 1 included i, it
The main function of the m circuit 513 is that the host system 50
The laser modulation circuits 514 and 521C send print data starting from 0 to one rear on a predetermined photoconductor 200 in accordance with the size of the paper to be printed. In addition, 1 necessary for the laser light output stabilization circuit of the laser modulation circuit 514 and 521.
Issue 11 will be sent out. It also sends timing signals necessary for sending print data to the host system 500. In FIG. 12, 830 is the laser modulation amount 't8514
．． 521 and print data 8 included atl 1111 circuit 51
This is to an input/output capo 1 for sending and receiving signals necessary for control within the controller 3. 831 is the writing of print data υ
It consists of a counter 1 timer that performs control such as control and radar light output sampling, and the setting of the operation mode and the preset value of the counter 1 timer is CPt.
J501 allows you to do it in an easy-to-understand manner. Is 865 a laser light output sample tie? r goo 1 ~ input G
The beam detector QH8YD, which is the output of the beam detector circuit 517, is input to 6, and the timer operation starts after the beam detector QH8YD, which is the output of the beam detector circuit 517, goes from LOW to HIGH level, and the timer operation ends. is set to terminate before the beam detector 518 for next beam detection. Therefore, the timer 865 is activated every time the beam detection signal H8YO is input to the gate input G6. A clock of 1500K)-17 is input to the clock input CK6 of the timer 865. Output S of the timer 865
MPTD is input to one of the 2OR gates 877, and the output of the 20R gate 877 is the first sample signal SAMP.
10. Loser modulation circuits 514 . Second laser modulation circuit 517:
2NAND gates 886 and 887. The other input of the 2NAND gate 886 is the output second laser diode enable signal @LD of the I10 port 830.
ON11 is input, and the first sample signal S
It is now possible to prohibit AMP10. Similarly, the two laser diode enable pull signals LDONZI are input so that the second sample signal SAMP20 can be inhibited independently. Similarly, the 2NAND
The second laser diode enable signal LDON21 output from the I10 boat 830 is input to the other input of the gate 887, so that the second sample signal SAMP20 can be inhibited independently. Also, 2OR gate 87
The output laser test signal LDTS1 of the I10 boat 830 is input to the other input of the first semiconductor laser 302. The second semiconductor laser 303 can be forced to emit light. A second laser ready signal @LRDY20 is input to the I10 boat 830, and the first laser ready signal LRDYIO2 is inputted to the I10 boat 830. By determining the second laser ready signal, it can be confirmed whether each laser is emitting light. 866 is a D-type F/F that generates the line start signal LST1, which is set by the beam detection signal H8YO and reset at the rising edge of the sample timer output 8MPTO. 867 is a D-type F/F that generates a beam detection ready signal LDOT1, which is input to the I10 boat 830. The aforementioned F/Fs 866 and 867 are also reset by the output of the 2OR gate 869. The input of the 2OR gate 869 is the first . A second laser diode enable signal. A crystal oscillator 832 serves as a reference clock for image clock pulses, and its oscillation frequency is approximately 32 MHz. 834.
835 is a J-KF/F that constitutes a quaternary power unit, which rotates the output of the crystal oscillator 832 by 4 minutes and generates a first video clock VCKX21 (approximately 8 MH 7 ) occurs. 837.838 is the same J-KF/ as 834.835 above.
F constitutes a quaternary counter, but JKF/F837
Input to J- is an n-pit binary counter 845.
A carry-out output CO is inputted via an inverter 846. In J-KF/F834, 835, 837.838, when the input to J- is at HIGH level, its Q output toggles in synchronization with the clock input CK, and when the input to J-
When it reaches the W level, its Q output interrupts the toggle operation. As a result, the Q output second video clock signal VCKY21 of the connected J-KF/F838 is r
It becomes 5/4J, which means that it has been extended by 1/4 clock. The preset inputs DO to Qn of the n-bit binary counter 845 are supplied with the main power 0 of the n-bit latch 847.
0 to 0 ports are connected, and the setting value is set by CPU501.
You can set values according to [) ip-sw, etc. The above setting value is for one line (LSTl is HIGH)
(between levels) to set the carry-out number of the n-bit binary counter 845, and as a result, the number of f'5/4J clocks to be generated. Inverter 839. The shift register 840.degree. 2NOR gates 841 and 842 are circuits that provide a predetermined operation to the n-binary counter 845. The second video clock signal VCKY21 is used to correct the difference in scanning length +1+, Q2 between the two laser beams. In this case, a laser beam with a scanning length of pl is supplied with the first video clock signal VCKX21. A second video clock signal CK is used for the laser beam of Ω2 with a short scanning length.
All you have to do is specify Y21. Reference numeral 848 denotes a selector that specifies the selection using the output CHGCK of the I10 boat 830. Next, the correction method will be explained by giving an example. For example, if the scanning length of the laser beam 1 is 200 ml and the scanning length of the laser beam 92 is 1991011, the difference in scanning length will be 11. When the resolution is 12 lines/glI11, 12 dot clocks per 2400 dots (200x12), 1 laser beam with a short scanning length.
It is sufficient to extend the video clock signal VCKY21 of 1!2. Here, since one correction stretches 1/4 dots O, the correction of 1/4 dot clock is performed 12×4=48 times between 2400 dots D. Therefore, in the n-bit binary counter 845, the clock input CP of the n-bit binary counter is 1/
Since it is a 4-dot clock, its carryout is 9.
600 (2400x4) 4 while counting clocks
It is enough to output 8. In other words, the preset value should be set so that one carry occurs every 200 counts. 836 is a binary counter.The Q2 output HCT31 is an 8-dot clock (approximately IMH2) obtained by dividing the first video clock VCKX21 by 8. 863 is a left margin counter that can set the data maze starting point from the beam scanning starting point. 864 is a write margin counter that sets the data writing end point f from the beam scanning start point. The line start signal L S T 1 is applied to the gate input G4 of the left margin counter 863 and the gate/input G5 of the left margin counter 864. Clock input CK of the left margin counter 863
4 and the clock input CK of the write margin counter
The 8-dot clock HCT31 is input to 5. Both counters are 2 times different from the start point of data inclusion and the end point of data inclusion due to mechanical installation error of the beam detector 518.
The book and the beam are corrected at the same time. The correction of the error is D
If you change the settings of both τ counters according to the IR-3W etc., you can adjust it to the middle of 8 dots. The reason for setting the 8-dot clock at position 111 is that an 8-dot deviation C between the starting position of the j-tater and the ending position of the data 1 with respect to the paper is within the permissible range, and the above-mentioned error adjustment is also required. This is because it is easy to perform. The set value of the light margin counter changes depending on the paper size. 875 is a 2AND gate, and the input of -Ij is outputted from the 7-gin counter 863 to the above-mentioned reflex 1 and MCTO. The other input is the output R of the write margin counter 864.
MCTO is input through inverter 874 to J3, so the output of 875 to the 2A N D 1 represents a horizontal printing area. The output of the 2AND gate 875 is sent to the shift register 86.
8, the horizontal printing area signal (IPEN1) is shifted by four dot clocks and is output from the Q output. The horizontal printing area signal HP E N 1 is 0 bits (~CE large input of the binary counter 850 and shift register 8
54. Said ngotu 1 to binary counter 8
50, 2NAND gate 849, n-bit latch 85
1. For J-KF/F852, the data wrapping start point is 1 dora 1.
~It has a circuit configuration that allows unit shift, and J-K
The output of F/F852 is the first horizontal printing area signal HPEN
Output BI. The n-bit binary counter 850
The preset manual Qo-Qn is for setting the right shift shift number, and the output of the n-bit latch 851 is connected, and the setting value can be set by the CPU 501 according to the D 1p-SW etc. . Shift 1 to register 854
and shift register 855. The inverter 853 has a circuit configuration that shifts the horizontal print area signal HPENI by two dot clocks, and the output of the shift register 855 outputs the second horizontal print area signal HPENA1. This is because the first horizontal print area signal HPENBI is shifted to the right by two dot clocks even at the minimum setting value. The output of AND gate 857 is indicative of the first horizontal print area signal and the first video clock signal VC.
LKB1, one of the inputs of the AND gate 857 is the first horizontal print area signal 1-IPENB1. The other is the Y1 output of the selector 848. Also, AND gate 85
The output of 6 is the second video clock signal VCLKAI indicating the video clock signal of the second printing area valve, and one of the inputs of the AND gate 856 is the second water W printing area signal H.
PENA1. The other is the Y2 output of the selector 848. As described above, the first horizontal print area signal HPENB1. The first video clock signal VCLKB1 is used to correct errors in the scanning start points of the two laser beams. In this case, the second horizontal print fr4il! is applied to the laser beam S2, which has a fast scanning start point. ! Signal HPENA1. The second video clock signal V CL KAl is specified, and the first horizontal printing area signal HPENB is applied to the S+ laser beam with a slow scanning start point.
1. It is sufficient to specify the first video clock signal VCLKBI and adjust the error d. The selector 858 is a selector for making the specification, and is made by the output C)-IG12 of the 110 port 830. 859 to 862 are counters for setting the data writing start point and data writing end point in the vertical direction (paper advancing direction), and 859 is a counter for setting the data writing start point for the first color.
A page top counter 860 is a first page end counter that sets the data writing end point for the first color.861 is a second page top counter that sets the data writing start point for the second color.862 is the data for the second color. This is a second page end counter that sets the write end point. Gate inputs of each counter 859 to 862 (3o to G3 are the page top signal P which is the output of I10 boat 830)
TOP1 is connected. It is started by the VSYNC command. Clock manual clock of each counter 859 to 862 CKo”-C
A line start signal LSTI is connected to K3, and as a result, it is possible to count in the middle of one scanning line (in units of one dot). The method of setting each counter will be described later. 871 is a 2AND gate, one input is the output PTCT10 of the first page top counter 859, and the other input is the output PECT1 of the first page end counter 860.
0 through the inverter 870, and therefore, the output of the 2AND gate 871 becomes the first color vertical print area signal PENII. 873 is a 2AND gate, one input is the output PTCT2C of the second page top counter 861), and the other input is the output PTCT2C of the second page end counter 8.
2O is input through the inverter 872, and therefore the output of the 2AND gate 873 becomes the second color vertical print area signal VPEN21. The output PECT10 of the first page end counter and the output PECT2O of the second page end counter are input to the ■/○ boat 830, and after each counting operation is completed, the first color page end ft number IPEND10. Second
Color page end signal IPEND20 to host system 5
Send to 00. 878 is the first color horizontal synchronization signal IH8YNIO,
79 is a ZNAND gate that outputs the second color horizontal synchronization signal IH8YN20 to the host system 500. 880 is the first color video clock signal IVCLKIO
, 881 is the second color video clock signal IVCLK
20 to the host system 500'. 884 is 3N which sends the first color video data signal IVDTIO from the host system 500 to the seventh laser modulation circuit 514 as the first video data signal VDAT10.
It is an AND gate. 885 is 3N that sends the second color video data signal IVDT20 from the host system 500 to the second laser modulation circuit 521 as the second video data signal @VDAT20.
It is an AND gate. 888 is an inverter that sends a first loser diode enable signal LDON 10 to the first loser modulation circuit 514; 889 is an inverter that sends the second laser diode enable signal LDON20 to the second laser modulation circuit 521. FIG. 13 shows a timing chart of one essential signal for one page in the two-color printing mode, and FIG. 14 shows a timing chart of main signals for one line. Next, the operation of each section which is activated in response to a control command issued from the control section of the two-color L8P 199 will be described in detail according to the flowcharts shown in FIGS. 15 to 24. FIGS. 15 to 19 are Δ flowcharts showing the initial operation of the entire two-color LBP. FIG. 15 shows the self-diagnosis and warming-up processes of the two-color LBPI 99. In FIG. 15, an operator at J3 turns on the power supply 520.
When N7j is executed, the system program stored in the ROM 502 starts, and first, steps △101 to AlO
4 is executed, and when the door switch is ON (101 negative to step), door open processing (step A105) is performed, and jam processing is performed (step A105) when the lJL paper switch is ON, the manual stop switch is ON, and the bus sensor is ON. △106). If the test print mode is not in maintenance mode (step 107 is negative, 108 is set), the heater lamp that heats the constant flange device 221, which takes a relatively long time to reach the ready state, is turned on (step 111). ),
Warming alarm/processing is started, and then the fixing device 221
The motor and the sensitive motor 512 are turned on (step Δ112). Note that if you are in test print mode (
Step 107 affirmative), test print 1-processing is actual (j
(step Δ109), and if the mode is maintenance mode, maintenance processing is executed (step All0).
. When the open motor 512 is turned on and enters the C ready state (step A113), the plaid solenoid is turned on (step A114). Note that if the scan motor 512 does not become ready even after 30 seconds have passed since it was turned on (step A113 negative, A115 affirmative), trouble processing for the scan motor 512 is performed (step 116). After the subsequent delay processing (step 117), the drum motor of the photoreceptor 200, the developing device motor 425, the clutch of the first developing device 203, the clutch of the second developing device 206, and the static eliminator 21
Each of the No. 1 lamps is turned on (Step 118), and through delay processing (Step 119), the No. 1 loser diode 3 is turned on (Step 118).
02, the second laser diode 303, laser test, and pre-transfer band 74 device 208 are turned on (step Δ120). After the subsequent delay processing (step A121), the failure of the second laser diode 303 and the second laser diode 303 is determined by the monitor (step △122, AI 23)
, if normal (step A122 portrait, step A1
23 Portrait), check those beam detection ready with water W synchronization signal H3YNC (step A128). In addition, the first rule
If the diode 302 is faulty (step 122
If the second laser diode 303 is out of order (No in step 123), a second laser failure process (step AI25) is executed. In addition, the horizontal synchronization signal HS
If the beam is not detected at YNC (step 12
6 negative), beam detection failure processing (step AI 27)
is executed. Subsequent delay processing (step △129) 142, the separation band diffuser 209 is turned on (step A130), and through the W spreading processing (step A131), potential control during warming up as shown in FIG. 70 is executed. (Step A132). 4j Also, step A132 is a process to enable printing as quickly as possible during the first printing. After the subsequent delay processing (step A133), step A1
The process advances to steps 34 to A140. Hit, step A13
4, the pre-transfer charger 207. Transfer charger 208. Each of the stripping chargers 209 is turned off. Step Δ136
Here, the developer motor 425, the clutch of the first developer 203, the clutch of the second developer 206, the first charger 201 .
Each of the second chargers 204 is turned off. Step A1
38, the drum motor of the photoreceptor 200, the snow remover 211
, the first loser diode 302. Second laser diode 3
03. Each of the motors of the fixing device 222 is turned off. In step A140, the blade solenoid is turned off. Thereafter, when the fixing device 221 becomes ready (step 141 is affirmative), the self-diagnosis and A-setting up processes in steps Δ101 to A141 are completed, and the 16th
Proceed to the routine shown in the figure. FIG. 16 shows a two-color LBP1 for the host system 500.
99 and issues a print request when the status of each part is determined to be normal from the host system 500. In FIG. 16, first, a determination is obtained from the host system regarding the contents of status 5 (steps A142 to A1).
45). That is, in step A142, it is determined whether or not to replace the toner bag. If you need to replace it (
Step A142 (Yes), wait for the toner pack to be replaced (Step Al46>, replacement completed (Step A1)
46 (Yes, A147), the process proceeds to step A143. In step A143, it is determined whether the empty switch of the first developing device 203 is set to 0N10FF to determine whether or not there is no toner of the first color. If there is no first color toner (step A1
43 (Yes), check whether it is the second color mode based on status 1. Step Al 48) If it is the first color mode and two-color printing mode (Step A148, negative)
, the replenishment of the first color toner to the first imager 203 is completed (step A149 portrait), and the process proceeds to step A144 at A150. Moreover, if it is the second color mode (step A148 tentative decision), step A149. Skip step A150 and proceed to A144. In step A144, the second developing device 2
0N10FF of the empty switch 06 determines whether or not there is no second color toner. If there is no second color toner (determined for step A144), M1 determines whether or not it is the first color mode based on status 1, and step A151
), if the mode is the second color mode and the two-color printing mode (No in step A151), the second color toner supply to the second developing device 206 is completed (step A152 portrait, A153), and the process proceeds to step 145. If it is the first color mode (Yes at step A151), steps A152 and A153 are skipped and the process proceeds to step 145. In this way, if there is no abnormality in the toner status of the first developing device 203 and the second developing device 206, reception of commands from the host system 500 is permitted. (Step A145). If there is a command that specifies the first color mode (step A154), the first color mode is set to status 1 (step A157), and if there is a command that specifies the second color mode (step A151). ),
The second color mode is set for status 1 (step A158). Further, if there is a command specifying the two-color printing mode (step A156 affirmative), the two-color mode is set in status 1 (step A159). Then, in the following step A160, IPRD ¥ is turned on.
When the process of turning on IPREQ is executed, in the subsequent step A161, a process of determining whether IPRNT has been turned on is performed, and if it remains OFF (No in step A161), the process returns to step A142. If it is turned on (Yes at step A161), the print request is turned off (step A162) and the process proceeds to the print processing after the routine shown in FIG. In FIG. 17, steps A163 to A17
4, the processing after the warming-up processing routine is executed. In the following step A177, it is checked based on the status 1 whether the mode is the second mode or not. If the second color mode is not present (No in step A177), the clutch of the first developer/lit device 203 is turned on, the C first developer 203 is driven (step A178), and the process advances to step A179. If it is the second color mode (step A177 portrait), step A17
Skip step 8 and proceed to step △179. In step A179, it is checked based on status 1 whether the mode is the first color mode. If it is not the first color mode (No in step A179), the clutch of the second developing device 206 is turned on and the C second color mode! 206 is driven (step A18
0), proceed to step 181. If it is the second color mode, the process skips step 180 and proceeds to step 181. In step A180', bias table data regarding the toner color of the first developing device 203 is read, and in subsequent step A182, the read bias table data is set in the D/A converter 578, and in subsequent step A1
At step 83, the bias table data regarding the toner color of the second phenomenon unit 206 is read, and at the subsequent step Δ184, the bias table data sold by the flea is sent to D/A, j.
A process of setting the converter 584 is executed. After the subsequent delay processing (step A185), potential control before first printing as shown in FIG. 22 is executed (
Step A186). In the following step A187, it is checked based on status 1 whether the mode is the second color mode. If it is not the second color mode (No in step A187), the developing bias 409 of the first developing BI device 203 is turned on. (Step A188), and the process advances to step A190. If it is the second color mode (step A187 affirmative), step A188 is skipped and the process proceeds to step 190, and the second color mode is selected as shown in FIG. fl ln potential 1
．． i i will be performed (step A189)
. In step Δ191 following the delay processing in step 190, it is checked based on status 1 whether the mode is the first color mode or not. If it is not the first color mode (No in step A191), the developing bias 409 of the second developing device 206 is set to ONL<
Step A192>, proceed to step A194. If it is the first color mode (step A191 portrait), step △
192 and proceeds to step A194,
As shown in FIG. 22, the first charging potential! , + control will be performed (step A193). In step A194, it is determined whether the paper feed cassette is in the upper or lower stage based on the status 1, and when it is determined that the paper feed cassette is in the upper stage, the paper feed motor is driven in normal rotation.

[
Upper stage paper feeding is performed (step A195), and the process advances to step 199, and the paper feeding motor is turned off after the delay processing in step A208? (Step A209). When it is determined that the paper is in the lower stage, step Δ195 is skipped, and after delay processing (step Δ196), the paper feed motor is reversed and paper is fed in the lower stage (Step A19).
7), proceed to step 199 and proceed to step A20.
8 delay]! I! After that, the paper feed motor is turned OFF (step A209>. In step 199, it is checked by status 1 whether or not it is the second color mode. If the 26th mode is not 'C' (No in step A199), the delay processing in step A200 is performed. Afterwards, the process advances to step A202. If it is the second color mode (Yes at step A199), the process proceeds to step A202 after the delay processing at step A201. In step A202, beam detection ready is detected using the horizontal synchronization signal H3YNC, and the process proceeds to step A204. Note that if beam detection ready is not possible (No in step A202), beam detection failure@immediate is executed. In step A204, as shown in FIGS. 20 and 21, the page top counter, page 1 end counter,
Left machine, Kunta, lie 1 to margin counter, and 2 beam scanning long-sleeve honesty are set. In the following step A205, \/3YNC of status 1
Sets a request and becomes a VSYNC command holder (step A206>, from the host system 500 to the VSYNC command)
When the SYNC command is sent, the VSYNC request is reset (step A207). Subsequently, in step A210 of FIG. 18, counting of the 1 heb/bottom counter is started, and the cycle from C to C is started.Thereafter, it is confirmed by status 1 whether it is the two-color printing mode or not (step A211). Then, if it is the first color mode and the second color mode (step A211 negative),
The process proceeds to step A213, and if it is the two-color mode (step A211 is determined), the process proceeds to step A213, and at the same time, the first charging potential control as shown in FIG. 70 is repeated five times (step A212). In the following step 213, the second
Check whether it is in color mode. If it is not the first color mode (No in step 213), the process proceeds to step 216 after the delay processing in step A214, and if it is the second color mode (
After step 213 (portrait) and delay processing of step Δ215, the process proceeds to step 216. When J3 is in step 216 and the registration motor is ○N1 total counter is turned on, delay processing (A217)
Afterwards, the total counter is turned off and step A221
At the same time, after a delay corresponding to the paper size (A219), the registration motor is turned off (Step A220).
. In step A221, it is checked again whether the mode is the second color mode. If it is not the second color mode (step A22
1 negative), when the first page end is detected (step A222 affirmative), the first color image writing is completed and the IP
ENDI is output as a pulse (step A223), and the process advances to step Δ224. In step 224, it is checked whether the mode is the first color mode. If status 1 is the first color mode (step A22
4 portrait), when the first color 1-toner is present in the first developing device 203 (step A231 negative), even if there is no second color toner in the second developing device 206 (step A238 is fixed),
As shown in Figure 19, print request IPREQS
It is turned on (step A248). At this time, there is no toner of the first color in the first developing device 203 (Yes at Step A231) and there is no toner of the second color in the second developing device 206 (Yes at Step A232). The print ready IPRDY is automatically turned off (step A252). Moreover, even if there is no first color toner in the first current @ container 203 (step A231 affirmative), the second current! & If the second color toner is present in the container 206 (step A232 negative) and both the first and second colors are the same color (step A233 affirmative), a command for specifying the 20th print mode has been issued. At some point (step A234 portrait), the developing bias 409 of the first developing device 203 and its clutch are turned off (step A235), the charging potential control of the first charger 201 is stopped, and this first charger 201 is OFF (step A236), the second color mode of status 1 is set (step 7A237), and the print request IPREQ is
/10N (step A2/18). On the other hand, when there is toner of the first color in the first developer 3203 (No in step A231) and toner of the second color in the second developer 206 (No in step A238), the toner of the second color
If there is a print mode specification command (step A239
The developing bias 409 of the first developing device 1O3 and its clutch are turned off (step A235), and the charging potential control of the first charger 201 is stopped.
1 is turned off (Sten/A236), Sr-9 S1
The second color mode setting is executed (step A237), and the print request IPREQ is turned on (step A248). When it is determined that the second page end is detected (step A225 affirmative), the second color image writing is completed and the IPE
ND2 is pulsed (step A226>, and the process proceeds to step A227). If status 1 is the second color mode (step A22
7 (affirmative), the second developer (even if there is no second toner in the Φ device 206 (affirmative at step A240), the first toner in the first developer device 203
If there is color toner (No in step A241), and fl first colors and second colors are all the same color (step A2
42 gate setting), when the first package medium character [-do designation 2] cloak is taken out (step A243 portrait), the second developing device 20
The developing bias 409 of No. 6 and its clutch are turned off (step 244>, charging potential υ of the second i electric device 204).
control is stopped, and this second charger 204 is turned off (
After proceeding to step 245a>, the first color mode of status 1 is set (step A245b), a pudding request IPREQtfiON is executed as shown in FIG. 67 (step Δ248). Also, in step Δ227, status 1 is the first
If the mode is other than the color mode, the status 51. : Judgment whether there is no first color toner or not,
In step A229, it is determined based on status 5 whether or not there is no second color toner Fj. Step A
228. If A22 is 1/no dog, the pudding l-ready IPRDY is turned OFF as shown in FIG. 67 (step A252). Further, if 1 to ner of the first color and the second color are right (step A228 negative, 229 negative), the process proceeds to step A248, and at the same time, the second charged potential IIIJ as shown in FIG.
tll twice (go to step 230). Note that in the routine of steps A221 to A248, step A
By omitting the determinations in steps 232 and 242, even if the thicknesses of the first developing device 203 and the second developing device 206 are not the same color, continuous development can be performed by switching the developing device. In FIG. 19, print request 1 in step A248
After processing 0N1J from step 1 to IPREQ, IPRNT
Judgment process of keeping ON for 5 seconds (to step 21 $9. A2
50> is executed and IPRNT- is turned ON (Step A249), the IPRE
Q is turned off -C (step A251), and it is determined whether the print mode has been changed (step A266). If the print mode is changed (step A266)
Yes), return to step A177, and step A177~
During step A194, check the status 1 and
The developing device 203 or the second imaging device 206 is made ready for development. If the print mode has not been changed (step A26)
6 negative), return to step Δ194, and step A177
The processing from step 193 to step 193 is omitted. However, in any printing mode, b1 Sde and Tsubu A142 to A174 are also 111! Since the operation is repeated without performing the above operation, the recording operation is continued without stopping the two-color LBP 199 for 10 seconds. In contrast, step A249. determines that IPRNT is ON for 5 seconds. 8250) is executed,
If 5 seconds have elapsed (step A250), the process returns to step A142 after the stop processing from step A253 to step A265, and enters a standby state for commands from the host system 500. Also, if Print Ready IPRDY is OFF (
In step A252), since there is no need to create print 1 to glJ1, the process returns to step Δ142 after the stop processing in steps A253 to A265, and the status of the commands received from the host system 500 is determined. Figures 20 and 21 go to step 204 in Figure 17.
3 is a flowchart showing the processing of FIG. 11 in the subroutine shown in FIGS. 20 and 21.
, step 8101 to step B107, which sets the top margin by 111 adjustments, and step 8114 to step B107.
Step B119 1 to fine adjustment setting of the bottom margin, step 8120 to step B123 fine adjustment and setting of bottom margin, and step 812
4 - Coarsely adjust the left margin in step 8128 Sera 1
, step 8129 to step B131 to coarsely adjust the line (-margin), step 8132 to step 8136 to finely adjust line 1 to engine, and step 8137 to step B
The processing is roughly divided into two beam scanning correction set processing of 141, and the details thereof are as shown in the figure. That is, in the process of coarsely adjusting and setting the top margin in steps 8101 to 107, the first color top margin table data D 1 FIJIl? Shun (Step B
101), reads the top margin coarse adjustment switch (step B102), and reads the top margin coarse adjustment table data D2 corresponding to the switch (step B101).
03). In the subsequent step B104, the top margin coarse adjustment table data D2 is added or subtracted from the value of the first column top margin table data D1 to obtain the calculation result D3 (9). In the subsequent step 8105, the status 1 is set to the 2 column mode'c.
If not (No in step B105), the calculation result D3 is set in the first page top counter 859 (step B106), and the routine proceeds to steps 8108 to B113 for coarse adjustment of the bottom margin. Furthermore, if the status 1 is the two-color mode (step B105), the performance result D3 is transferred to the second page top counter 861.
(step 8107), and also in step B.
The routine advances to steps 108-B113. After reading the bottom margin table data D4 of the specified paper size in step 8108, in the subsequent step B109, the first column top margin table data D1 is added to the bottom and margin table data D4 to obtain a calculation result D5. In the subsequent step B110, the margin rough adjustment table data D2 is added to the value of the calculation result D5, and the calculation result rAD
Get 6. In the following step B111, if step 1 is not the second color mode (step B111 negative), the rotation result D6 is set to the first color mode.
Set the page end counter 860 (step B
113), the process advances to steps 8114 to 8119, a routine for finely adjusting and setting the top margin. Moreover, if step 1 is the second village mode (step B111 affirmative),
The calculation result D6 is set in the second page end counter 862 (step B112), and the process is also performed in step 8114.
Proceed to routine 819. When the second column top margin table data D7 is read in step B114, the top margin fine adjustment switch is read in the subsequent step B115, and in the subsequent step 811
In step 6, the top margin fine adjustment table data D8 corresponding to the switch is read. In the following step B117, the margin coarse adjustment table data D2 is immediately added to the second top margin table data D7.
and the fine adjustment table data D8 are added or subtracted to obtain the calculation result D9 (q.
The process advances to B123, the bottom margin fine adjustment set routine. Further, if the status 1 is the two-color mode (step 8118 affirmative), the calculation result D9 is set in the second page top counter 861 (step B119), and the routine similarly proceeds to steps B12O-B123. In step B120, the bottom margin table data D4
After adding the second column top margin table data D7 to obtain the calculation result D10, in the following step B121, the margin rough adjustment table D8 is added or subtracted from the value of the calculation result D1o to obtain the calculation result D11. If the status 1 is not the two-color mode in the subsequent step B122 (step B122 negative), steps 8124~
The process advances to the left margin coarse adjustment set routine of 8128. Further, if the status 1 is the two-color mode (step B122 affirmative), the calculation result D11 is set in the second page end counter (step B123), and the routine similarly proceeds to steps 8124 to 8128. In step B124, left margin table data D1
2 is read, and in the subsequent step B125, the left margin coarse adjustment switch is read IC, and in the subsequent step 8126, the left margin coarse adjustment data D13 corresponding to the switch is read. In the subsequent step B127, the margin rough adjustment table D13 is added or subtracted by 0 to the value of the left margin tail data D12 to obtain a performance and a result D14. In the subsequent step B128, the dripping result D14 is set in the left margin counter 863, and steps 8129 to
The process advances to B131, the light margin coarse adjustment routine. In step B129, the light margin table data D15 of the specified paper size is read, and in the subsequent step 8130, the rough margin adjustment table data D13 is added to or subtracted from the value of the light margin table data D15, and the operation C1 is completed! g! : Obtain D16. Next, in step B131, the result D16 is input to the Lydon counter 864, and the routine proceeds to steps 8132 to 8136 for fine adjustment and setting of the margin. In step B132, the left 7-gin@,;nu switch is read, and in the subsequent step B133, the left margin fine 'A adjustment table data D17 corresponding to the switch is read, and in the subsequent step B134, the value of the table data D17 is latched to the n-bit latch 851. Set to . In the subsequent step B135, the print rrJ area changeover switch is read, and in the subsequent step 8136, the I10 boat 830 is changed from Sera 1 to Sera 1 to return according to the print area changeover switch in Step 8136.
37 to B141, the routine proceeds to the two-beam scanning distortion correction routine. After reading the 2-beam scanning good correction switch in step B137, the scanning length correction table data D18 corresponding to the subsequent step 8138'c switch is read, and this table data D18 is set in the n-pitch latch 847 in the subsequent step B139. In the subsequent step B140, the dot clock changeover switch is read, and in response to this dot clock changeover switch, the subsequent step B141r changes the 1/'0 boat 830 to the cellar 1~, and the process of step A204 shown in FIG. 17 is performed. will end. FIG. 22 shows the voltage control during warm-up and the voltage control before first printing. The fortune-telling Q system 00 at the time of warming up reads the first Rakuden initial-II allll output value CHI)T from the table data (step C101), and uses the read value as O7.
・′△-]Set to the engine bark 576 step C1
02). In addition, the value C of the second charging initial & 41 III output
H]) D2 from the table data; sell (Ste Tub C103), and convert the reading value to D/'82 converter 582
Step 0104). When the first charger 201 is turned on in the subsequent step ClO3, the first charging potential control is executed as shown in FIGS. 23 and 24 (step Cl06). The subsequent delay processing (
After step C107), step C108r second band T
h When the device 204 is turned on, the second charging potential control is executed as shown in FIGS. 23 and 24 (Step C
'109),. Then, I(l/a, 1ltl11 times n steps 1fL(
Step C110), until this potential υ1011 number of times n reaches 3 times, r i; The unit 204 is turned off (step C112), and the upper level control at the time of 4-mink-up ends. For potential control before first printing, if status 1 is not the second color mode (step D101 negative), the first
The charger 201 is turned on (step D102), and the seventh
As shown in FIG. 1 and FIG. 72, the first charging potential control 0 is executed (step 1] 103), and if only the first color mode is present (portrait of step D104),
"+'+Fj's electronic samurai system iIl ends. Also, if it is a two-color mode (step D104 is negative)
, after the R extension process (step 0105), the second charger 20
4 is turned on and the second
The charging potential control n is executed (step D107), and the potential υj bullet before the first print ends. Also, if status 1 is the second color shade in the first step D101, only the second color shade is executed.
The second charger 204 is turned on (step D106),
As shown in FIGS. 23 and 24, the second charging potential a11
The control is executed (step D107), and the potential control before the first print is completed. FIG. 23 and FIG. 24 show details of the charging potential control process. - It is. In the subroutine shown in FIGS. 23 and 24,
First, the A/D converter 593 detects the drum temperature detector 570.
is selected (step E101), and the photoreceptor 200
temperature measurement is performed (step E102). Then, either the first charging potential control or the second charging potential control is selected (step E103). Based on the data table in the ROM 503, in the case of the first charging potential control, each of steps 104 to E109 is selected. the process is executed,
In addition, in the case of second charging potential control, steps 113 to 113
Each process of step E118 is executed. And step E110 and step E119? - are the first to correspond to the actual temperature of the photoreceptor 200, respectively.
The target surface potential data (VO81) and the second target surface potential data (VO32) are corrected to obtain corresponding correction data VO31- and vO82'. In the following steps E111 and E120, the storage capacity obtained in steps 104 to E110 and the storage capacity 1q obtained in steps E113 to E11 are stored in a common register, so the steps shown in step E111 and step E120 are performed. A number of arithmetic operations are executed. In the following steps E112 and E121, A/
The D converter 593 selects the first potential sensor 202 and the second potential sensor 205, respectively. Next, regardless of whether it is the M1 charging potential control or the second charging potential 1iull charge, each process from step 122 onwards is executed. First, 1. A delay process is executed for a time corresponding to the travel distance between the second charger 201, 204 and the first and second charger level sensors 202, 205, and the first. The surface potential Vs is measured by the second surface sensors 202 and 205 (steps E122 and E123>. In the following steps, step E111 and step E
Processing is performed based on each data shown at 120. That is, in step E124, a self-diagnosis is performed to determine whether the read value is greater than or equal to VO3+VOMAX, according to the arithmetic expression: Vs≧Vos+■o111AX. If it is above (Step E124 affirmative)
, execute potential control error processing. (Step E125
), if it is less than (step E124 negative), the process advances to step E126. In step E126, it is determined whether the read value is within the target value and the control range of the error table according to the formula Vs=VO3+Voz. If not (step E126 negative), check step by step how much, for example, 200V, 100V, 50V deviates from the target (steps E127 and E128).
．． E129), the control port is set to the same size as ΔX1 or Δ×2), or twice, four times, and six times, respectively (step E130.E131.E132.E).
133). After this setting, the process proceeds to step E134, where charging is performed 7J. The force is set, and in the following step E135'r it is checked whether the charging output is greater than the maximum value, and in the following step E136 it is checked whether the charging output is 6 less than the minimum value, If it is too big or too small (Stetsubu E135 portrait), Stetsubu E136t
1), potential control error processing is executed (step E137). If the charging output is within the control range (step E135 negative, step E136 negative), step E1
38, it is determined whether the actual potential control target is the first charger 201 or the second charger 204. If this determination result is the first charger 201, CHo T
After setting I = CHO r (step E139), set C)-1 electric knife 1 to D/
The process of setting the A converter 576 is executed, and the process proceeds to step E145. Also, if this determination result is the second charger 204, CF+
1) T 2 = CHI) Setting of T (
(Step E141), Cl-11) TI to D2'
The process set in the A converter 582 is completed (j is completed,
The process advances to step E145. In step E145, the number of times of charging potential control is incremented, and the routine proceeds to step 150 in FIG. 24 (YES). That is, if the potential is controlled from first purine 1 to before (step F141 constant), °1 position ii++ 1211 times m
, step E151 is set three times), and the throat adjustment by potential control is completed, and the second paralysis returns to Step F[122. In addition, when the potential υl1ll at the time of warming up is set (step 154), the potential control target m is 10 times 7
:' (step 150 affirmative), potential control error processing is executed (step E153), and if it is repeated 9 times, the process returns to step E122. Furthermore, if status 1 is not two-color mode (step E148 negative), the process returns to step E122, but if status 1 is two-color mode (step 148 affirmative),
Potential control targets are the first charger 201 and the second charger 204
If it is the first charger 201, the potential control ends when the potential control is performed five times (step 150 is affirmative), and if it is the second charger 204, the potential control is performed twice. When this happens (step 154), potential control ends. As described above, in one embodiment of the present invention, two-color L
The 8P199 interface circuit 519 sends a video clock signal (IVCLKl, IVCLK
2) The host system 500 requests the transmission of one dot of LC print data, and the host system 500 generates a video data signal (IVD) of the dot image data based on the video clock signal, etc.
ATl, IVDAT2) to the interface circuit 519
It is designed to be sent to. Therefore, in order to change the printing start position on two-color LBP199'C paper, the host system 500 does not need to perform Rffi processing to change the number of pulses of video data No. 13 and its sending timing. A video data signal is sent from the host 1-system 500 to the two-color LBP 199 in synchronization with the video output signal from the two-color LBP corresponding to the size. Therefore, the increase in the program capacity Q in the host system 500 can be suppressed by υ1, and the waiting time when starting and overturning the printing operation (1) which is not taken into account can be suppressed as much as possible. 2JJ !l!!] As described above, the image forming apparatus to which the present invention is applied outputs a video clock signal from the printing side in which the number of output b pulses changes depending on the paper size, and Video data 1 is sent from the host side to the printing side based on the clock signal.
Since the system configuration is such that the number Δ is sent out, even if the paper size changes on the printing side, the host side can easily respond to the change in paper size.

[Brief explanation of the drawing]

FIG. 1 is a block diagram schematically showing an embodiment of an image forming apparatus to which the present invention is applied, FIG. 2 is a block diagram not showing the system configuration of a two-color LBP applied in one embodiment, and FIG. The figure is RO
FIG. 4 is a diagram showing the details of the interface signal between the interface circuit and the host system, FIG. 5 is an explanatory diagram of the relationship between the interface signal and the data input position, and FIG. FIG. 7 is a detailed explanation diagram of the commands used in the two-color LBP. FIG. 8 is a block diagram showing details of the laser modulation circuit and semiconductor laser. A circuit diagram showing details of a beam detection circuit and a beam detector,
FIG. 10 is a diagram showing the relationship between the scanning range of the laser beam, the beam detection position, and the data writing position;
Fig. 11 is a diagram showing the positional relationship of data writing positions on the entire paper, Fig. 12 is a circuit diagram showing details of the print data writing control circuit, and Fig. 13 is a print data writing control signal in two-color printing mode. Figure 14 is a timing chart of the data write control signal for one line, Figure 15 is a timing chart of the data write control signal for one line.
Figures 19 to 19 are flowcharts showing the overall operation of the two-color LBP, Figures 20 and 21 are page top counters,
Figure 22 shows the subroutine for hitting the page end counter, left margin counter, right margin counter, and 2-beam scanning length correction value.Figure 22 shows the subroutine for potential control during warm-up and potential control before first printing. Flowchart, No. 23
24 and 24 are flowcharts showing a subroutine for controlling the charging potential, and FIG. 25 is an explanatory diagram of a conventional image forming apparatus. 199...Two-color LBP 500...Host system 519...Interface circuit

Claims (2)

[Claims] (1) Consisting of a printing side and a host side that sends various data signals to this printing side, the printing side outputs a video clock signal whose output pulse number changes depending on the paper size, and this video clock An image forming apparatus characterized in that a video data signal is sent from the host side to the printing side based on a signal. (2) The number of video clock signals outputted by the printing side is equal to the number of video data signals outputted from the host side to the printing side in response to the video clock signals. The imaging device described.