JPH07195803A - Power on-of controller - Google Patents

Abstract

PURPOSE:To prevent print data from being lost by disconnecting power supply after all data to be printed in a storage of a printer is printed. CONSTITUTION:An input controller 14 always monitors commands from a host unit 26, if it is a print command, stores the print command and print data delivered from the host unit 26 sequentially in a storage means 16, or if it is a power supply disconnect command, stores control data corresponding to the power supply disconnect command in the last of print data stored in the storage means 16. An output controller 18 takes out those data stored in the storage means 16 sequentially, if the data are print data, process them sequentially, or if the data are control data corresponding to the power supply disconnect command, delivers a power supply disconnect command to the main power supply controller 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply on / off control device, and more particularly to a power supply on / off control device for cutting off the power supply of a printing device according to an instruction from a host device.

[0002]

2. Description of the Related Art A printing device (for example, a printer, etc.) is instructed by a host device such as a host computer.
As for a power on / off control device for turning on (turning on) or turning off (off) a power source of a facsimile device, a copying machine, an image printing device, etc., as described in JP-A-4-275613, an interface cable is used. A power on / off control device including a signal monitoring circuit that constantly monitors a power on / off signal from a host computer via a power supply, and a power on / off circuit that is connected to the signal monitoring circuit to turn on / off the power of the printing apparatus. It has been known.
According to this power on / off control device, the power of the printing device is immediately cut off by the power off signal from the host computer.

At present, print data from a host computer is sequentially stored as a spool file in a disk storage device in the printing apparatus, and print data input processing and print data output processing (print processing) are executed asynchronously. Allows the printing speed of the printing device to be
In addition, a printing apparatus is generally used that can communicate with a host computer without waiting for a print job to make the printer unit of the printing apparatus available.

[0004]

However, in the printing device having the spooling function, as described above, the power on / off control device immediately turns off the power of the printing device in response to the instruction to turn off the power from the host computer. In this case, the following problems will occur. That is, in the spooling function of the printing device, when the print data from the host computer is stored in the storage device, the completion of the I / O request is reported to the host computer that sent the print data. The print data is still stored in the storage device, and the actual print processing has not been completed. However, the host computer recognizes that the printing process is completed by being notified of the completion of the above-mentioned I / O request, sends an instruction to turn off the power to the printing apparatus, and immediately turns on the power of the printing apparatus. When disconnected, the print data existing in the storage device may be lost without actually being printed. The same problem applies to the printing device described in Japanese Patent Laid-Open No. 4-275613.

Therefore, the present invention has been made in view of the inconveniences of the above-described prior art, and its object is to send the power to the printing apparatus when the power is turned off by the instruction to turn off the power sent from the host apparatus. Another object of the present invention is to provide a power on / off control device capable of preventing lost print data from being lost in the printing device.

[0006]

A power on / off control device according to the present invention is a storage device for storing data, a main power supply control unit for controlling a main power supply in response to a request, and a command from a host device at all times. If the command is a print instruction command, the print data sent from the host device together with the print instruction command is sequentially stored in the storage means, and if the command is a power-off instruction command, An input control unit that adds control data corresponding to the power-off instruction command to the end of the print data stored in the storage unit and stores the data sequentially stored in the storage unit, and the data is the print data. In some cases, the print data is sequentially printed, and if the data is control data corresponding to the power-off instruction command, the main power And a, and an output control unit for sending a power-off request to the control unit.

[0007]

According to the above configuration, the input control section constantly monitors the command from the host device, and if the command is the print instruction command, the print data sent from the host device together with the print instruction command. Are sequentially stored in the storage means, and when the command is a power-off instruction command, control data corresponding to the power-off instruction command is added to the end of the print data stored in the storage means and stored. The output control unit sequentially takes out the data stored in the storage unit, and if the data is print data, sequentially prints the print data and controls the data to correspond to the power-off instruction command. If it is data, a power-off request is sent to the main power control unit. Therefore, since the power-off request is sent to the main power supply control unit by extracting the control data corresponding to the power-off instruction command after the printing process of all the print data is completed, the print data remains in the data storage unit when the power is turned off. Print data is not lost.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.
It will be described based on.

FIG. 1 schematically shows the construction of a printing apparatus 10 of a first embodiment such as a page printer provided with a power on / off control device 12 according to the present invention. The printing apparatus 10 includes a power on / off control device 12 and a printer unit 22. The power on / off control device 12 includes an input control unit 14 and a data storage unit 16.
And an output control unit 18 and a main power supply control unit 20.

The input control unit 14 is connected to a host computer 26 as a host device, and stores data sent from the host computer 26 in the data storage unit 16. The output control unit 18 reads out the data stored in the data storage unit 16 and outputs the data to the printer unit 22. The printer unit 22 prints the data sent from the output control unit 18. The main power supply control unit 20 takes in power from the outside via a plug 24, and turns on or off the power supply of the data storage unit 16 and the printer unit 22, that is, the main power supply, in response to a request from the input control unit 14 and the output control unit 18. To Further, the main power supply control unit 20 supplies power to the input control unit 14 and the output control unit 18 via a power supply line (not shown) even when the main power supply is cut off.

Next, the operation of the power on / off control device 12 in the printing apparatus 10 of the first embodiment having the above-mentioned configuration will be described.

The input controller 14 is a host computer 2
The print data sent together with the print instruction command from 6 or the control command sent from the host computer 26 is converted into a predetermined data block format as a print data block or a control data block,
The completion of the I / O request is reported to the print job of the host computer 26, and those data blocks are chained and stored in the data storage unit 16 in the order sent from the host computer 26. When the power-off instruction command is transmitted, the input control unit 14 cannot accept any print instruction command and subsequent print data until the power-on instruction command is transmitted thereafter. That is, it is reported that the I / O request was not accepted for the print job of the host computer 26 even if the print instruction command was sent.

Here, a state in which data blocks are chained in the data storage unit 16 will be described. Figure 2 (a)
FIG. 6 is a diagram illustrating an example of a structure of a data block stored in a chain in the data storage unit 16. The contents of the area of the head data block address, that is, the "head data block address", includes the host computer 2 first.
The start address of the first data block corresponding to the print instruction command and print data or control command sent from # 6 (here, since the disk storage device is used, this is the absolute sector number of that data block)
Is stored. The start address of the second data block is stored in the "next data block address" of the first data block. If the data block does not exist in the data storage unit 16, data such as X'00 'indicating that the data block does not exist is stored. Thus, at present, the data storage unit 16
All the data blocks stored in are linked in the order sent from the host computer 16, and the "next data block address" of the last data block indicates the end of the data block. Mark (for example, X'in hexadecimal notation here)
00 ') is stored. In the "print data", if the data block is a print data block, the print data is stored, and if it is a control data block, only the data indicating what kind of control is stored is stored. May be indefinite data. Figure 2
FIG. 2B shows the meaning of the data stored in the “data type” of each data block shown in FIG. 2A, and if the hexadecimal representation X′80 ′ is stored, that data block is shown. Indicates a print data block, and if X'40 'is stored, the data block is a control data block. In addition, X'0 is set in the "next data block address" of the data block.
If 0'is stored, it means that the data block is the last.

Next, the operation of the input control unit 14 will be described in more detail with reference to the flowchart of FIG. First,
In step 100, the command sent is waited for, and if the command is sent, it is determined whether the command is a print instruction command. If it is a print instruction command, the print instruction command and print data are fetched into a reception data buffer (not shown) of the input control unit 14 in step 102, and the print data is converted into an internal format in steps 104 and 106, that is, in the input control unit 14. Is mapped to the image buffer for one page (not shown). Then, in step 108, the completion of the I / O request for the print data is reported to the print job of the host computer. And step 11
At 0, it is judged whether or not the image buffer for one page is completed, and if not completed, the process returns to step 100 to wait for the next print instruction command and print data to be sent. In this way, each time print data such as character data, graphic data, image data, etc. is sent out, it is converted to the internal format (for example,
(Character code data, vector graphic data, etc. are converted into dot information), mapped to the image buffer, the completion of I / O request is reported, and data for page break is sent out to generate one page. When the print data for one minute is completed, in step 112, the data storage unit 16 is used for the "next data block address" of the print data block having the data block end mark (X'00 ') at the "next data block address" at the present time. A new print data block is added by writing the address of the available space as the next data block address. Then, X'80 'indicating the print data block is written as the "data type" in the new print data block, and X'00 indicating the end of the data block is written in the next "next data block address". 'Is written and is created in the image buffer in the "print data" 1
Write print data for a page. Then, in order to process the print instruction command for the next page and the print data or the power-off instruction command, step 1
Return to 00.

If the command sent in step 100 is not a print instruction command, it is determined in step 114 whether it is a power-off instruction command. If it is a command other than the power-off instruction command, in step 122 the command is issued. The process corresponding to the command is executed and the process returns to step 100. In step 114, if it is the power-off instruction command, step 11
6, it is determined whether the image buffer of the data storage unit 16 is currently empty. If there is print data being created in the image buffer, a process similar to the process in step 112 described above is executed in step 118,
Add a new print data block. Then, in step 120, a control data block is added next to the new print data block by the method described above. Further, this control data block has an X'4 indicating "control type" as the "data type".
0'is written and X'0 indicating the end of the data block at the next "next data block address" is written.
0'is written, "print data", for example, X'FF 'indicating a power-off instruction command, is written at the leading byte position, and the process ends. If Step 11
In 6, if the current image buffer is empty,
After branching to step 120, the process of step 120 described above is executed and the process ends.

By transmitting the power-off instruction command in this manner, the control data block corresponding to the power-off instruction command is added to the end of the chain of data blocks in the data storage unit 16.

Next, the operation of the output controller 18 will be described. The data blocks stored in the data storage unit 16 are read from the data storage unit 16 by the output control unit 18 in order from the one stored first, that is, the one sent first from the host computer 26, for example, by the first-in first-out method. If the read data block is a print data block, it is sent to the printer unit 22 and actually printed. In this printing process, other processes are not executed until the printing is completed. If the read data block is a control data block, the process designated by the control data block is executed. If the control data block corresponds to the power-off instruction command, the output controller 18 sends a power-off request to the main power controller 20.

Now, the operation of the output control section 18 will be described in more detail with reference to the flow chart of FIG.
The output control unit 18 outputs the print data block to the printer unit 22 if the printer unit 22 is available and the print data block to be output exists in the data storage unit 16. In step 201, first,
"Start data block address" shown in FIG. 2 (a)
To determine whether there is a data block. If there is no data block in the data storage unit 16, it waits until the data block is stored from the input control unit 14. If there is a data block, the data block input first is read first. In step 202, it is determined whether the read data block is a control data block or a print data block. If it is a print data block, in step 204, the "print data" of the print data block is set to the printer unit 22.
Output to and print. Then, in step 206, the process waits until the printing process is completed. In step 208,
Printing is completed by holding the "next data block address" of the print data block for which printing has been completed and changing the contents of the "starting data block address" to the "next data block address" held in step 208 in step 210. The created print data block is deleted from the data storage unit 16 and the process returns to step 200 to read the next print data block. This process is repeated, and if the control data block is not completely detected in step 202, the host computer 26
Means that the power-off instruction command has not been sent from the host computer. If the power-off instruction command has been sent from the host computer 26, the control data block corresponding to the power-off instruction command exists in the last data block. Should be. Therefore, step 212
In step 214, the control data block corresponding to the power supply instruction command is detected after printing of all print data blocks is completed, and in step 214, the output control unit 18 requests the main power supply control unit 20 to turn off the main power supply. To delete the control data block. The process branches to step 215 for other control data blocks, executes other control processing, for example, power-on instruction processing, and returns to step 200.

In this way, the main power supply of the printing apparatus 10 can be turned off after all the print data blocks existing in the data storage unit 16 have been printed, and the print data can be stored in the data storage unit 16 without being printed. Print data is not lost because it is not left behind.

The main power supply control unit 20 cuts off the main power supply of the printing apparatus 10 taken in from the outside through the plug 24 in response to a power-off request from the output control unit 18.

When the power-on instruction command is sent from the host computer 26 to the input control unit 14 with the main power supply of the printing apparatus 10 turned off, the input control unit 14 executes step 122 in FIG. The process of turning on the main power source is executed. That is, the input control unit 14 sends a power-on request to the main power supply control unit 20. The main power supply controller 20 turns on the main power supply of the printing apparatus 10 in response to the power-on request.

Note that, in FIG. 3, only a search for tracing a chain of data blocks in the forward direction can be performed, but each data block has a data block address area for tracing in the reverse direction, and a power-off instruction command exists. The processing speed for determining whether or not it may be improved. Alternatively,
By providing the directories corresponding to the respective data blocks, the processing speed of the disk device search is further improved.

In the above embodiment, the case where the control data block corresponding to the power-off instruction is stored in the data storage unit 16 as the last data block has been described. However, as an application of the present invention, for example, the output control unit is It is constantly inspected whether or not the control data block corresponding to the power-off instruction is present in the data block, and if it is detected, all the print data blocks existing in the data storage unit 16 at that time are printed. A process of sending a power-off request for cutting off the main power source to the main power source control unit 20 is also conceivable.

A second embodiment of the present invention applied to the printing apparatus 30 connected to a plurality of host computers will be described in detail below with reference to FIGS. Here, the same symbols are used for the same components as in the first embodiment.

FIG. 5 is a block diagram showing a printing device 30 provided with the power on / off control device 12 according to the present invention. In the figure, a plurality of host computers 1, 2,
3, ... are the respective interface cables 32
It is connected to the printing device 30 via ₁ , 32 ₂ , 32 ₃ ... Interface cables 32 ₁ , 3
A signal line for sending an instruction signal for turning on or off the power of the printing device 30 from each host computer is provided in each of 2 ₂ , 32 _3, ...
A signal line having a predetermined number is assigned in advance as a / OFF instruction signal line.

Each power ON / OFF instruction signal line 3
2 _1, 32 _2, 32 _3, ... are connected to the power source ON / OFF instruction updating unit 34 in the printing apparatus 30. Also,
A data signal line used for transmitting data is connected to the power on / off control device 12. Power ON / OF
The F instruction updating unit 34 constantly monitors the instruction signal transmitted from each host computer via the power ON / OFF instruction signal line, and when the instruction signal is transmitted from any of the host computers, the instruction storage unit 34 The contents of the area of 36 corresponding to the host computer are updated to the contents according to the instruction of the instruction signal.

The instruction storage unit 36 includes an instruction management table having the table structure shown in FIG. In FIG. 6, the total number of host computers currently connected to the printing device 30 is stored in the “total number” of the first field on the first line. Data indicating the current power supply state of the printing device is stored in the "current power supply state" of the second field in the first row, and if the hexadecimal display X'80 'is stored, the printing device is displayed. It indicates that the power supply of 30 is on, and that if the hexadecimal display X'40 'is stored, it is off. From the second line of the instruction management table, the "host computer name" of the first field stores the "host computer name" of each host computer, and the "instruction status" of the second field.
Stores the data indicating the instruction state of the power supply of the printing apparatus, which is currently instructed by the host computer, stored in the first field. In this second field, if the hexadecimal display X'80 'is stored, the host computer has instructed to turn on the power supply, and the hexadecimal display X'40' is stored. For example, the host computer has instructed to turn off the power.

Next, the power ON / OFF judging section 40
By referring to the instruction management table at the present time from the instruction storage unit 36, it is determined whether the power of the printing apparatus 30 should be turned on or off at the present time, and if necessary, the instruction management table of the instruction storage unit 36 The “current power state” is updated, and control data for turning the power on or off is transmitted to the input control unit 14 of the power on / off control device 12. Input control unit 1 of power on / off control device 12
When receiving the control data for turning off the power from the power ON / OFF determination unit 40, the control unit 4 stores the control data block in the data storage unit 16 in the power ON / OFF control device 12.
The input control unit 14 of the power on / off control device 12 is
The print data blocks sent from the respective host computers via the data signal lines are stored as print data blocks in the data storage unit 16 in the power on / off control device 12. The output control unit 18 in the power on / off control device 12 reads out the data stored in the data storage unit 16 and outputs it to the printer unit 48. The printer unit 48 prints the data sent from the output control unit 18. The main power source control unit 20 in the power source on / off control device 12 includes the plug 4
A power source is taken in from the outside via 4 and the power source of the data storage unit 16 and the printer unit 48, that is, the main power source is turned on or off in response to a request from the input control unit 14 and the output control unit 18. Further, the main power supply control unit 20 keeps the input control unit 14 and the output control unit 1 even when the main power supply is turned off.
8, power ON / OFF instruction update unit 34, instruction storage unit 3
6, and the power ON / OFF determination unit 40 is supplied with power through a power supply line (not shown). The output control unit 18 sends a power-off request for cutting off the main power supply to the main power supply control unit 20 in the power-on / off control device 12 by detecting the power-off control data block. The power on / off control device of the printer unit 48 is
In response to a power-on request or a power-off request from the power-on / off determination unit 40, the external power source taken from the plug 44 is turned on or off.

The operation of the printing device 30 having the power on / off control device 12 will be described below with reference to the drawings. The power ON / OFF instruction updating unit 34 constantly monitors the instruction signals transmitted via the respective power ON / OFF instruction signal lines 32 ₁ , 32 ₂ , .... This is, for example, to detect a voltage level state in which the power-on / off instruction signal is a power-on instruction while the power-on / off instruction signal is in an H-level state and is a power-off instruction while the power-on / off instruction signal is in an L level state. May be done by Alternatively, it may be done by interpreting a predetermined field of a data block transmitted in a predetermined format through the data signal line of the interface cable. Power ON /
When the OFF instruction update unit 34 detects that the instruction signal is sent from any of the host computers by the change in the state of the voltage level, the instruction storage unit 3
The "instruction state" in the instruction management table 6 corresponding to the host computer is updated according to the state of the voltage level. This operation is executed regardless of whether the "current power supply state" in the instruction management table is ON or OFF.

The power ON / OFF judging section 40 of the printing device 30 is based on the content of the instruction management table of the instruction storage section 36 by updating the content of the instruction management table stored in the instruction storage section 36. Whether the power is turned on or off is determined, and if necessary, the contents of the “current power state” of the instruction management table are updated and the input control unit 14 of the power on / off control device 12 is notified.

FIG. 7 is a flow chart for explaining an embodiment of the processing executed in the power ON / OFF judging section 40. Below, based on FIG. 7, power ON / OF
The operation of the F determination unit 40 will be described. In step 300, the power ON / OFF determination unit 40 always reads the instruction management table stored in the instruction storage unit 36 and determines whether the "instruction state" has been updated. If it has not been updated, the next reading is performed.
If it has been updated, in step 302, the "current power supply state" is read from the instruction management table and the current power supply state is checked. If the current power is on, the process branches to step 304. If the current power is off, the process branches to step 306. In step 304, it is determined whether all "instruction states" in the instruction management table are off. If all the “instruction states” are off, a power-off instruction for turning off the power is sent to the input control unit 14 in step 308. Then, in step 310, the "current power supply state" of the instruction management table is changed to off, the process returns to step 300, and the next reading is performed. If all "instruction states" are not off in step 304, that is, if there is at least one "indication state", the process is terminated and the next cycle is waited. If the process branches to step 306 in the determination of step 302, it is determined in step 306 whether or not the instruction management table has an “instruction state” of ON.
If at least one “instruction state” is on, step 312
In step 1, a power-on instruction for turning on the power is sent to the input control unit 14. Then, in step 314, the "current power supply state" of the instruction management table is changed to on, and the process returns to step 300 to perform the next reading. If there is no ON content in step 306, that is, if all contents are OFF, the process returns to step 300 and the next reading is performed.

In FIG. 7, the power ON / OFF judging section 40
Has described that the power ON / OFF is determined by reading the contents of the instruction state table of the constant instruction storage unit 36. However, the power ON / OFF is not determined by reading the contents of the constant instruction state table. Instruction update unit 3
4 may read the contents of the instruction state table in response to the notification that the instruction state table has been changed and make the above determination. Alternatively, the above-mentioned determination may be performed by reading the contents of the instruction state table at a constant cycle.

Input control section 14 in the power on / off control device
When receiving the power-off instruction inputted as a result of the operation of the power-on / off determination unit 40, the power-off control data block is stored at the end of the data blocks stored in the data storage unit 16. The output control unit 18 in the power on / off control device sends a power cutoff request for cutting off the main power supply to the main power supply control unit 20 by detecting all the print data blocks and then detecting the control data blocks. .

The main power supply to the printer unit 48 is actually switched by a signal input from the main power supply control unit 20 and the output control unit 18 of the power supply ON / OFF control device 12 to request turning on or off of the main power supply.

In this way, the main power supply is cut off only when all the connected host computers are sending the power supply OFF instruction signal, and after the control data block for the power supply cut is detected, the main power supply is cut off. It is possible to prevent the power from being cut off easily, and the power is not cut off by leaving the print data block to be printed by the printer unit 48 in the data storage unit 16.

In the second embodiment described above, it is explained that it is determined whether or not the main power source of the printing apparatus is turned off by the instruction to turn on or off the power source from a plurality of computers. May be determined by recognizing what the current power status of the computer is.

[0037]

As described above, according to the present invention, when the power-off instruction of the printing apparatus is sent from the host apparatus, the power-off processing is executed after all the print data is printed. Can be prevented from being lost.
When the printing apparatus is not used, the printing apparatus is automatically powered off, so that power consumption can be saved.

[Brief description of drawings]

FIG. 1 is a block diagram of a power on / off control device for a printing apparatus according to the present invention.

FIG. 2 (a) is a diagram for explaining a chained state of data blocks, and FIG. 2 (b) is a specific example of data stored in a data block for identifying the type of data.
It is a figure which shows the specific example of the termination mark stored in the following data block address.

FIG. 3 is a flowchart illustrating an operation of an input control unit.

FIG. 4 is a flowchart illustrating an operation of an output control unit.

FIG. 5 is a block diagram of a printing apparatus according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a structure of an instruction management table.

FIG. 7 is a flowchart illustrating a process for determining whether to turn on or off the power supply in the printing apparatus according to the second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 printing device 12 power supply ON / OFF control device 14 input control unit 16 data storage unit 18 output control unit 20 main power supply control unit 22 printer unit 26 host computer (upper device) 30 printing device 48 printer unit

Claims (1)

[Claims] 1. A power supply on / off control device for controlling on / off of a main power supply of a printing device connected to a higher-level device, the storage device storing data, and a main power supply for controlling the main power supply in response to a request. The control unit and the command from the host device are constantly monitored, and if the command is a print instruction command, the print data sent from the host device together with the print instruction command are sequentially stored in the storage means. If the command is a power-off instruction command, an input control unit that adds control data corresponding to the power-off instruction command to the end of the print data stored in the storage unit and stores the control data. The data stored in the storage means is sequentially taken out, and if the data is print data, the print data is sequentially printed and the data There wherein when the power-off instruction command the corresponding control data, an output control unit for sending a power-off request to the main power supply control unit, the power-off control device provided with a.