JPS6275590A - Sentence display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention particularly relates to a text display device that displays text related to the operating procedure or operating status of a copying machine on a display section provided on an operation panel of a copying machine.

[Technical Background of the Invention] In recent years, copying machines have become more multifunctional, including variable magnification, double-sided copying,
Various models have been developed that can perform advanced editing processing in combination with partial deletion and the like.

By the way, as copying machines become more multi-functional, the operating procedures are becoming more complex, and when users actually want to perform editing processing, they are often unable to immediately determine the operating procedures to achieve that goal. .

Under these circumstances, a model has recently been developed that displays text related to operating procedures or operating conditions in a question-and-answer format on the display section of the operation panel P, as shown in FIG.

According to this model, the user can perform the desired editing process without hesitation simply by operating according to the text displayed on the display unit.

[Problems with the Background Art] However, the text display device described above operates a large number of shift registers at extremely high speeds to display on a fluorescent display tube, and the types of text that are actually displayed are quite limited. As the number of devices increases, the circuit system of the device becomes extremely complex. For this reason, the control circuit of the apparatus may malfunction due to noise caused by static electricity or the like during the copying operation. If a malfunction occurs in the control circuit, it will inevitably result in incorrect display, but if such a problem occurs, the user must perform a recovery operation by turning off the device's power and then turning it on again. There was a problem in that the copying process had to be interrupted.

[Purpose of the Invention] The present invention has been made to solve the problems of conventional text display devices.Even if the control circuit malfunctions due to noise caused by static electricity, etc. The purpose of the present invention is to provide a text display device that does not require interrupting the process.

[Summary of the Invention] That is, the text display device of the present invention includes: a display tube for inputting character pattern data and displaying the character pattern; a shift register in which the character pattern data to be output to the display tube is sequentially set; A latch that outputs the character pattern set in the shift register to the display tube according to a strobe signal, a control circuit that periodically outputs the character pattern data and the strobe signal, and a branch input of the strobe signal from this control circuit. and a reset circuit that outputs a reset signal to the control circuit when the strobe signal is no longer output at a normal cycle based on a predetermined time constant, and recovery processing of the control circuit is automatically performed. This is how it was done.

[Embodiments of the Invention] Hereinafter, details of embodiments of the present invention will be described based on the drawings.

FIG. 1 is a circuit diagram showing the configuration of a drive system of an apparatus according to an embodiment of the present invention.

This circuit includes a fluorescent display tube that displays text related to the operating procedures or operating status of the copying machine], drivers 2a and 2b that apply a driving voltage to the fluorescent display tube 1, a shift register 3a13b with a built-in latch, A microcomputer 4 that outputs character patterns and timing signals through each shift register input/output port (Ilo), an overall control section 5 that controls the entire copier, a reset circuit 6 to be described later, and a microcomputer 4. R
The transistor Tr has a collector connected to an 8T (reset) terminal.

The fluorescent display tube 1 of this embodiment is a dot character type fluorescent display tube, and is a triode electron tube in which a cathode, a grid, and an anode are enclosed in a high-vacuum glass container. The cathode (filamerent) is an ultra-fine tungsten wire, and the grid is a thin metal mesh.
The 7 nodes are made up of segmented dots on which phosphor is coated so that numbers, letters and symbols can be displayed.

In this fluorescent display tube 1, thermoelectrons emitted from the cathode are accelerated by the electrostatic voltage applied to the grid and the anode, and the phosphor coated on the 7 nodes is stimulated to emit light.
By selectively applying voltage to the anode and grid, desired numbers, letters and symbols can be displayed. Note that the luminescent color of the phosphor is blue-green, and the resulting display is bright and clear.

Roughly speaking, the fluorescent display tube 1 of this embodiment has 35 characters (5x
7) It is composed of dots, and the number of characters that can be displayed at one time (hereinafter referred to as the number of digits) is 40.

When a display is to be performed on the fluorescent display tube 1, a character pattern is first output from the input/output port of the microcomputer 4 to the shift register 3a on the anode side seven times in parallel in 5 bits each, completing the setting of the character pattern. The character pattern is then transferred to an internal latch. Then, write " in the shift register corresponding to the first digit on the grid side.
1" is set and the output on the grid side becomes 1ON", the first digit character is displayed on the fluorescent display tube 1.

In this case, all 39 shift registers other than the shift register corresponding to the first digit on the grid side are set to "O".
is set.

This operation is repeated sequentially until the 40th digit.
When the 40th digit is reached, the process returns to the 1st digit and the same operation is repeated again.

In the device of this embodiment, only the shift register on the anode side is connected in two stages: a shift register and a latch.
The character pattern already written in the shift register is transferred to an internal latch to start displaying, and while the display is being performed, the next character pattern is written in the shift register.

Furthermore, in the device of this embodiment, when the INT (interrupt) signal of the microcomputer 4 becomes "Trubel", the microcomputer 4 receives data from the overall control section 5,
When the ACK (acknowledgment) signal is set to "Trubel" and the ACK signal becomes "Trubel" in response, the INT signal returns to "Trubel").When the microcomputer 4 judges the display content, the ACK signal is set to "Trubel" again. ”.

In this way, a new sentence is displayed on the fluorescent display tube 1.

By the way, as shown in FIG. 2, the microcomputer 4 used in the device of this embodiment has a stable power supply voltage, for example, when using an oscillator of 6 MHz or higher, the R3T The instruction is executed when the (reset) terminal is held at "Trubel" for more than 24 clock cycles and changed to the (IrTrubel).

That is, in FIG. 1, R of the microcomputer 4
The reset signal applied to the base of the transistor Tr inserted before the 3T terminal is the power supply voltage (+5V)
Even after it stands up, it remains in the ``Trubel'' for a while. Therefore, when the power supply voltage rises, the transistor Tr is in an OFF state for a while, and the R3T terminal of the microcomputer 4 becomes "Trubel".

Thereafter, the reset signal becomes "Trubel", the transistor Tr is turned on, and the cathode extension j of the diode D1 becomes "Trubel".

Furthermore, as will be described later, the cathode side of the diode D2 is also at "truvel" at this point, so the microcomputer 4 starts operating normally.

Next, the reset circuit 6 will be explained.

This reset circuit 6 is composed of two monostable multivibrators M1 and M2. Since the human power A of the multivibrator M1 is fixed at "Trubel", when the human power B changes from "Trubel" to "1L level", output JQ changes from "Trubel" to "Trubel".

Here, the "truvel" duration time of the output Q is determined by the time constant of the externally attached resistor RI and capacitor C1.

Also, since the human power B of multivibrator M2 is fixed to "Trubel", the input A changes from "Trubel" to "Trubel".
When the output Q changes from “Tolbel” to “Tolbel”, the output Q changes from “Tolbel” to “
It changes to "Trubel".

It should be noted that the time period during which the output Q continues to be in the "trubel" state is determined by the time constants of the externally attached resistor R2 and capacitor C2.

In addition, input B (pin 5) of multivibrator M1 is the STB (strobe) of shift register 3a on the anode side.
connected to the terminal.

STB (strobe) input to the STB terminal here
Explain about signals.

As shown in FIG. 3, in this embodiment, the STB signal output from the microcomputer 4 is synchronized with the OE (output enable) signal and CLK (clock) signal output to the grid-side shift register 3b. The data set in the shift register 3a on the anode side is output to the fluorescent display tube 1 at the latch timing based on this STB signal.

The time constant determined by the resistor R1 and capacitor C1 of the multivibrator M1 is set larger than the output period of the ST8 signal, and the input A (
4 pin) is always fixed at the "Trubel" level, so the output O is always at the 1L level.

That is, in the device of this embodiment, when the microcomputer 4 is operating normally, the STB signal is periodically input to the human power B, so the output 0 (pin 7) of the multivibrator M1 is always at the "L level". "become.

This output (m (7 pin) is connected to the input A (12 pin) of multivibrator M2, and the human power B (11 pin)
is fixed at the "H level", so the output Q (pin 10) of the multivibrator M2 is always at the "L level".

In addition, if the microcomputer 4 is not yet operating after the power supply voltage has been raised, the output 0 (pin 7) of the multivibrator M1 becomes "H level", and the output Q (pin 10) of the multivibrator M2 becomes "H level". "L level"
It remains as it is.

By the way, during operation of the device, if the microcomputer 4 ceases to operate normally due to the influence of noise caused by static electricity or the like, the STB signal will not be output periodically.

Then, the output Q (pin 7) of the multivibrator M1 of the reset circuit 6 changes to "H level", and the output Q (pin 10) of the multivibrator 2 also changes to "H level" for a time constant determined by the resistor R2 and capacitor C2. Changes to "H level". This time constant is considered to be sufficient time to reset the microcomputer 4, and once the microcomputer 4 is reset, it starts executing instructions again.

In this embodiment, the microcomputer 4 shifts the output cycle of the STB signal when outputting the ACK signal, and the microcomputer 4 periodically outputs the STB signal as long as it is normal to prevent erroneous reset. At the same time, the ACK signal is kept at "L level" for 10m5, and then set to "H level".

Furthermore, the overall control unit 5 that controls the entire copying machine checks the ACK signal at a 5 mS cycle, and if the ACK signal is at "L level" even though no data is being sent, Wait for the ACK signal to go to "H level" and send the data. Therefore, even if the microcomputer 4 is reset again, the current text will remain on the fluorescent display 1.
will be displayed.

However, in the device of this embodiment, the microcomputer 4
Even if the fluorescent display tube 1 malfunctions due to the influence of noise, it will return to normal operation in a short time that the user will not notice.
The operating procedure and operating status of the copying machine are displayed again.

[Effects of the Invention] As explained above, the text display device of the present invention branches the strobe signal from the control circuit and inputs the strobe signal to the control circuit when the strobe signal is no longer output at a normal cycle based on a predetermined time constant. Equipped with a reset circuit that outputs a reset signal, even if the control circuit malfunctions due to noise caused by static electricity, etc., the control circuit is instantly reset and operates normally, and the Yuna switches off the copier's power supply. Copying operations can be continued without performing recovery processing that temporarily drops the data.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing the configuration of the drive system of a device according to an embodiment of the present invention, FIG. 2 is a timing chart showing the relationship between the power supply and reset signal in the device according to the embodiment, and FIG. 3 is a circuit diagram showing the configuration of the drive system in the device according to the embodiment. FIG. 4 is a perspective view showing the arrangement of a display section of a text display device in a conventional copying machine. 1...... Fluorescent display tube 2a,
2b... Drivers 3a, 3b... Shift 1 to Register 4... Microcomputer 5... Overall Control unit 6...
・・・・・・・・・・・・Reset circuit Tr・・・・
......Transistor D1, D2...Diode R1, R2...Resistor C1, C2...Capacitor

Claims (2)

[Claims] (1) A display tube into which character pattern data is input to display the character pattern, a shift register into which the character pattern data to be output to the display tube is sequentially set, and a shift register into which the character pattern data set in the shift register is displayed. a latch that causes the display tube to output according to the strobe signal;
A control circuit that periodically outputs the character pattern data and a strobe signal, and a control circuit that branches the strobe signal from the control circuit and when the strobe signal is no longer output at a normal cycle based on a predetermined time constant. A character display device comprising: a reset circuit that outputs a reset signal to the circuit. (2) The character display device according to claim 1, wherein the reset circuit comprises a monostable multivibrator configured in two stages.