JPH0619723A - Output device - Google Patents

Abstract

PURPOSE:To simultaneously execute output and interruption by generating interruption in accordance with the level of an output signal. CONSTITUTION:A signal from a frequency generator 13 is supplied to a counter 1, and a signal from a pulse generator 14 is supplied to the reset terminal of the counter 1. Data from data sources 2a-2c are supplied to a data latch 4 through a data bus 3, and the index of data is supplied to a data latch 5. A signal from the data latch 5 is supplied to a comparator 6 and it is compared with the count value of the counter 1. Compared output when they coincide is supplied to an output latch 7 and a signal from the data latch 4 is latched. A signal from the output latch 7 is supplied to a microcomputer(CPU) 9 through an output port 8. Furthermore, an arbitrary output signal from the output latch 7 is supplied to an edge detection circuit 10. A signal from the edge detection circuit 10 is supplied to the interruption terminal of CPU 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an output device which outputs a large number of programmable signals in synchronization with a periodic signal.

[0002]

2. Description of the Related Art It is known that an output device that outputs a large number of programmable signals in synchronization with a periodic signal generates an interrupt at every output timing. However, there was nothing that generated an interrupt at the same time as outputting to a port.

When a signal from the output device is supplied to a microcomputer for processing, a specific output is interrupted. However, there was nothing that outputs that specific output at the same time when the interrupt is generated.

[0004]

The problem to be solved is that none of them generate an interrupt simultaneously with outputting.

[0005]

According to a first aspect of the present invention, in an output device which outputs a large number of programmable signals in synchronization with a periodic signal, an interrupt is generated in synchronization with the level of an arbitrary output signal. The output device is characterized in that

According to a second means of the present invention, in an output device which outputs a large number of programmable signals in synchronization with a periodic signal, an edge detecting means to which an arbitrary output signal is supplied is provided, and the edge detecting means ( The output device is characterized in that the circuit 10) detects a change in the level of the arbitrary output signal and generates an interrupt by using the detected signal.

In the third means according to the present invention, the periodic signal is a signal from the frequency generator 13 of the rotary head drum 11, and the pulse generator 14 of this rotary head drum is used.
The output device according to the first or second means is characterized in that the output of which the level of the arbitrary output signal is changed is output at the timing of the signal from.

According to a fourth means of the present invention, the periodic signal is a signal from the frequency generator 22 of the stepping motor 21, and the level of the arbitrary output signal is changed at the timing of stopping the stepping motor. The output device according to the first or second means is characterized in that the output is output.

[0009]

According to this, an interrupt can be generated simultaneously with outputting.

[0010]

1 shows an example in which the invention of the present application is applied to drive control of a rotary head drum. In this figure, 11
Is a rotary head drum, 12 is a drum motor (M), 13
Is a frequency generator that detects the rotation speed of the motor 12 (F
G) and 14 are pulse generators (PG) for detecting the rotation phase of the motor 12. And these frequency generators 13
Also, a signal from the pulse generator 14 is supplied to the servo circuit 15 to control the rotation of the motor 12.

In such an apparatus, it is considered to control the entire apparatus in synchronization with the driving of the rotary head drum 11. That is, the signal from the frequency generator 13 described above is supplied to the counter 1. Also pulse generator 1
The signal from 4 is supplied to the reset terminal of the counter 1. Here, the signal from the frequency generator 13 is a periodic signal, and the interval between the pulse signals from the pulse generator 14 is 6
Or 12 or 18 periodic signals are generated.

On the other hand, 2a, 2b and 2c are data sources of each part of the apparatus, and data from these data sources 2a, 2b and 2c are supplied to a data latch 4 through a data bus 3. Further, indexes are attached to each of these data, and these indexes are supplied to the data latch 5.

Then, the signal from the data latch 5 is supplied to the comparator 6 and compared with the count value of the counter 1. When they match, the comparison output is taken out. This comparison output is supplied to the output latch 7, and the signal from the data latch 4 is latched.

As a result, a large number of outputs are programmable and output to the output latch 7 in synchronization with the periodic signal from the frequency generator 13. The signal from the output latch 7 is output through the output port 8 to a microcomputer (CPU).
9 is supplied.

Further, an arbitrary output signal from the output latch 7 is supplied to the edge detection circuit 10. Then, the signal from the edge detection circuit 10 is supplied to the interrupt terminal of the microcomputer 9.

Therefore, in this apparatus, for example, the above-mentioned arbitrary output signal is set to the "H" level only when the data of the timing when the counter 1 is reset by the signal from the pulse generator 14 and is set to the "L" for the other data. By setting the level, the output of this data can be detected by the edge detection circuit 10 and the microcomputer 9 can perform the interrupt processing by this detection signal.

Thus, according to the above-mentioned device, an interrupt can be generated at the same time as the output.

That is, in the above-mentioned device, the microcomputer 9 can perform the interrupt processing at a desired timing. As a result, for example, when the conventional specific output is discriminated and the interrupt processing is performed inside the microcomputer, it becomes difficult to perform accurate processing due to a time delay until the determination, and It is also possible to easily calculate the interrupt timing and the like.

FIG. 2 shows an example in which the invention of the present application is applied to drive control of a stepping motor. In this figure, 21 is a stepping motor, 22 is a frequency generator (F
G) and 23 are control circuits of the stepping motor 21.

In this device, the signal from the frequency generator 22 is supplied to the counter 1. Further, a signal from the microcomputer 9 is supplied to the control circuit 23. Others are the same as the above-mentioned device.

Here, the rotation of the stepping motor 21 is stopped when the signal from the frequency generator 22 reaches a predetermined number. Therefore, by setting an arbitrary output signal of data when the count value of the counter 1 reaches a predetermined number to be "H" level, the microcomputer 9 can perform the interrupt processing at this timing. Then, the interrupt processing supplies a stop signal to the control circuit 23 to stop the rotation of the stepping motor 21.

As a result, accurate rotation control of the stepping motor 21 without time delay can be performed.

In addition to the above, the invention of the present application is the same as the first invention.
And a device driven using the second periodic signal.

[0024]

According to the present invention, it becomes possible to generate an interrupt at the same time as outputting.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an example of an output device according to the present invention.

FIG. 2 is a configuration diagram of another example of the output device according to the present invention.

[Explanation of symbols]

 1 counter 2a, 2b, 2c data source of each part of device 3 data bus 4 data latch 5 data latch 6 comparator 7 output latch 8 output port 9 microcomputer (CPU) 10 edge detection circuit 11 rotary head drum 12 drum motor (M) 13 Frequency generator (FG) 14 Pulse generator (PG) 15 Servo circuit 21 Stepping motor 22 Frequency generator (FG) 23 Control circuit

Claims (4)

[Claims] 1. An output device that outputs a large number of programmable signals in synchronization with a periodic signal, wherein an interrupt is generated in synchronization with the level of an arbitrary output signal. 2. An output device, which outputs a large number of programmable signals in synchronization with a periodic signal, is provided with an edge detecting means to which an arbitrary output signal is supplied, and the edge detecting means detects the above-mentioned arbitrary output signal. An output device characterized in that a level change is detected and an interrupt is generated by using this detection signal. 3. The periodic signal is a signal from a frequency generator of the rotary head drum, and the output of which the level of the arbitrary output signal is changed at the timing of the signal from the pulse generator of the rotary head drum. The output device according to claim 1 or 2, characterized in that 4. The periodic signal is a signal from a frequency generator of a stepping motor, and an output in which the level of the arbitrary output signal is changed is output at a timing at which the stepping motor is stopped. The output device according to claim 1 or 2, characterized in that.