JPH1021181A - Terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To unnecessitate any complicated circuit or special software for interruption from an input/output device by sending out an interruption signal to an interruption signal line in the state of non-use in response to the generation of interruption request. SOLUTION: An interruption control circuit 101 puts the interruption signals from the input/output device in order and performs interruption control to a computer. The interruption signals from control parts from 1-3 to 1-4 are directly connected to the signal lines of an interruption signal group 2 corresponding to their respective priority levels. The signal lines of the interruption signal group 2 respectively have the priority levels. The input/output device except high-priority input/output devices from 1-1 to 1-4 sends the interruption signal through an interruption output circuit 3 to the interruption control circuit 1-1. A control part 4 of the interruption control circuit 3 has a circuit for automatically recognizing the potential levels of respective signal lines of the interruption signal group 2, detects the non-used signal line and generates interruption on that signal line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal device of a computer system, and more particularly to a terminal device having an interrupt control line recognition function.

[0002]

2. Description of the Related Art With the recent increase in the number of functions of devices mainly including CPUs, it is required to connect a large number of input / output devices to one device. In order to perform interrupt control for each input / output device, a method of assigning a priority level to an interrupt signal from each input / output device, providing a priority control circuit for each priority level, and transmitting an interrupt signal is used. However, the circuit scale increases as the number of input / output devices increases.

Japanese Patent Application Laid-Open No. 5-35649 proposes a method as shown in FIG. 3, an interrupt priority level is set in advance by a level setting unit 101 for a plurality of input / output devices. Thereafter, when an interrupt signal is input from a plurality of input / output devices, the priority level is added to the input interrupt signal by the set level factor generation unit 102. In addition, the input factor detection unit 104 causes the input factor select count unit 103
The coincidence between the count value counted by the above and the interrupt signal is detected, and the interrupt signal currently being input is detected.

[0004] The interrupt level signal generator 105
As a result, the currently input interrupt level signal is generated from the signal output from the set level factor generation unit 102 and the current interrupt signal detected by the input factor detection unit 104, and the interrupt level signal transmission unit 106 From the interrupt level signals output from the level signal generation unit 105, one of the interrupt level signals having the same priority level is selected and output.

[0005]

In the conventional interrupt control system shown in FIG. 3, a circuit for setting an interrupt priority level on a terminal device connected to an input / output device, and determining the priority level of an input interrupt signal. Since a circuit, a circuit for counting input factors, and the like are required, there is a problem that the terminal device becomes complicated. Also, there is a problem that software for processing an interrupt after an interrupt signal is input must be special for the interrupt control circuit.

An object of the present invention is to provide a terminal device that does not require a complicated circuit and does not require special software for an interrupt from an input / output device.

[0007]

According to the present invention, there is provided a terminal device which receives an interrupt request from an input / output device and selectively sends an interrupt signal to one of a plurality of interrupt signal lines. A use state detecting means for detecting the use state of each of the interrupt signal lines, and an interrupt signal is transmitted to the non-use state interrupt signal line by the use state detection means in response to the generation of the interrupt request. And a transmitting device.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The operation of the present invention is as follows.
The control circuit that controls the input / output device determines the potential level of the interrupt output signal line before using the interrupt, searches for a signal line that can output an interrupt, and then searches for a free interrupt output signal line. Use to output an interrupt signal.

Further, the software for controlling the interrupt can be used only by shifting the interrupt priority level without being changed.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of a terminal device according to the present invention.

In FIG. 1, an interrupt control circuit 1-1
Arranges interrupt signals from the input / output device and controls interrupts to a computer (CPU) (not shown). The interrupt signal group 2 is a signal line (path) for inputting an interrupt signal from the input / output device to the interrupt control circuit 1-1, and includes a plurality of signal lines. As shown in FIG. 2, in the case of the embodiment of the present invention, the interrupt signal group 2 is shown by seven signal lines for explanation, but the present invention is not limited to this.

Each signal line of the interrupt signal group 2 has a priority level (order), and conversely, each signal line is identified by the priority level of the signal line.

The terminal device 1 includes, in addition to the interrupt control circuit 1-1, a high-priority input / output device (keyboard (KB) 1-
4-1, mouse 1-4-2, hard disk drive (DI
SK) 1-4-3, floppy disk drive (FDD) 1
-4-4, etc.), and the interrupt signals from these control units 1-3-1 to 4-4 correspond to the signals of the interrupt signal group 2 according to the respective priority levels. Directly connected to the line (highest priority connection).

The above-mentioned high-priority input / output device 1-4-1
Input / output devices (not shown) other than the input / output devices 4 to 4 output interrupt signals via the interrupt output circuit 3 to the interrupt control circuit 1-1.
Send to The control unit 4 of the interrupt output circuit 3 has a circuit for automatically recognizing the potential level of each signal line of the interrupt signal group 2, detects an unused signal line, and generates an interrupt on the signal line. be able to.

FIG. 2 is a detailed block diagram of the control section 4 of the interrupt output circuit 3. The interrupt output section 5 receives an interrupt output request signal from an input / output device and outputs an interrupt signal to the interrupt signal group 2. The output level is controlled by the interrupt level identification unit 6.

The interrupt level discriminating section 6 is a circuit which judges the potential level of each signal line of the interrupt signal group 2 and judges whether or not the signal line is currently used. The interrupt factor output unit 7 is a circuit that generates an interrupt signal in response to an interrupt output request signal from an external input / output device. The interrupt level notification circuit 8 is a signal line of the interrupt signal group 2 to which an interrupt signal is actually output. (Priority level thereof) to the terminal device 1.

The interrupt control circuit 1-1 detects the input of an interrupt signal when the potential level of each signal line of the interrupt signal group 2 rises from low to high. Each signal line of the interrupt signal group 2 becomes low (level) when the control unit 1-3-1 to 4 or 4 that outputs an interrupt (signal) is connected, and when not connected, High (level).

Therefore, when any input / output device intends to input an interrupt signal via the interrupt output circuit 3, the control unit 4 determines in advance the potential level of each signal line of the interrupt signal group 2 by the interrupt level identification unit 6. , Avoid signal lines that are low (level), high (level)
Is output via the interrupt output unit 5 to the signal line (priority level).

If a plurality of signal lines are high (level), a signal line having a higher priority level is selected. The selected signal line (priority level) can be recognized from the terminal device 1 via the interrupt level notification circuit 8. Terminal device 1
The interrupt control software on the side sets a program execution location, a priority, and the like based on the priority level (signal line) notified from the interrupt level notification circuit 8.

When the processing of all the interrupt signals is completed, all the signal lines of the interrupt signal group 2 have been used first, and the result that the interrupt signal could not be sent to the interrupt control circuit 1-1 Also, the terminal device 1 can be informed by the notification from the interrupt level notification circuit 8.

Further, the interrupt control circuit 1-1 can restrict the reception of the interrupt signal by outputting low (level) to the signal line of the interrupt signal group 2 during the software processing. This can prevent the occurrence of operation abnormality due to too many interrupt inputs.

[0023]

As described above, the present invention has an effect of organizing interrupt signals from a large number of input / output devices without using a complicated circuit.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a detailed block diagram of a control unit of the interrupt output circuit.

FIG. 3 is a block diagram illustrating an example of a conventional interrupt control circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Terminal device 1-1 Interrupt control circuit 1-3-1 to 4, 4 Control unit 1-4-1 Keyboard 1-4-2 Mouse 1-4-3 Hard disk device 1-4-4 Floppy disk device 2 Interrupt signal Group 3 interrupt output circuit

Claims (2)

[Claims] 1. A terminal device for receiving an interrupt request from an input / output device and selectively transmitting an interrupt signal to one of a plurality of interrupt signal lines, wherein a use state of each of the interrupt signal lines is provided. And a transmitting unit for transmitting an interrupt signal to the non-used interrupt signal line by the using state detecting unit in response to the generation of the interrupt request. Terminal device. 2. The terminal according to claim 1, wherein said use state detection means detects a signal level of each of said interrupt signal lines, and identifies a use state according to the detected level. apparatus.