JPH01158551A - Input/output control system - Google Patents

Abstract

PURPOSE:To simplify a microprogram for an input/output control and to facilitate a debugging and a function addition by providing a control memory circuit to store the top address of an input/output control processing program necessary or the data transfer control of plural input/output devices. CONSTITUTION:A processor 2 reads control data through a control data line 8 from the address of a control memory 4 assigned with information lines 6, 7 and 10. The read control data indicates the top address of an input/output control processing program, and a microprogram jumps to the address. The processor practices an input/output control processing by practicing the input/ output control program of the jumping destination, after the input/output control processing ends, sets information to indicate the next input/output control condition in the information line 6, and shifts to the next processing. Thus, the complicated input/output control processing is attained, the micro program can prepare the input/output control condition without being conscious for each input/output control processing, and the addition of the debugging and the function of the program is facilitated.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an input/output control method, particularly an input/output control system using a microprogram-controlled processing device to which multiple input/output devices that require complex data transfer control are connected. Regarding control method.

[Conventional technology]

Conventional input/output control methods of this type include the flag sense method, which prepares flags or bits that display the status of input/output devices and performs input/output control while monitoring those flags, and the flag sense method, which controls input/output while monitoring the flags, and the flag sensing method, which controls input/output by monitoring the flags or bits that display the status of input/output devices. When an input/output device is ready, it starts a program that controls input/output, executes other processing without waiting for its completion, and uses interrupts to generate an interrupt to the processing device when the input/output device completes its input/output operation. There is a method according to

[Problem that the invention seeks to solve]

The conventional flag sense method described above requires complex data transfer control, such as processing when an abnormality occurs in an input/output device, or processing when the meaning of information indicating the operating status of the input/output device differs depending on the data transfer sequence. When used for multiple input/output devices, the number of flags or bits that display the status of the input/output devices increases, and the meaning of the flags or bits may differ depending on the data transfer sequence, so it is difficult to control the input/output. This poses a problem in that the microprograms for this are complicated, and the number of microprograms required for one flag sensing is large, making debugging difficult.

In addition, in the case of a method that uses interrupts, it is more effective than the flag sense method when you want to operate multiple input/output devices simultaneously and eliminate input/output waiting time and waste time, but In order to simplify the input/output control program by processing all transfer control using interrupts, there is a drawback that an interrupt control circuit having many interrupt lines is required.

An object of the present invention is to eliminate the problems of the above-mentioned flag sensing method when performing complex data transfer control, simplify the microprogram for input/output control, and provide an input/output system that facilitates debugging and function addition. The objective is to provide an output control method.

[Means for Solving the Problems] The method of the present invention is an input/output control method that performs complex data transfer control using a microprogram for multiple input/output devices. A control memory is provided to store control data for each address determined by the control state and the operating state of each input/output device, and the microprogram has an input/output control program whose start address is the control data. reading control data from the control memory and executing an input/output control program specified by the control data;
It is characterized in that it then operates to set the next input/output control state.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, which is comprised of a ROM 1 storing a microprogram, a processing device 2, two input/output devices 3 and 4, and a control memory 4. FIG.

A processing device 2 controlled by a microprogram in a ROM 1 is connected to input/output devices 3 and 9 via a bus 5. Further, the control memory 4 stores control data necessary for data transfer control of the input/output devices 3 and 9, and its address line is connected to an information line 6 indicating the input/output control state set by the microprogram, Equipment 3 and 9
The processing device 2 can read the contents of the control memory 4 at any time through the control data line 8.

The control memory 4 contains control data equal to the number of matrices formed by the information line 6 indicating the input/output control status and the information lines 7 and 10 indicating the operating status of the plurality of input/output devices 3 and 9, and contains control data corresponding to the number of microprograms. has input/output control processing programs equal to the number of matrices.

Next, the operation of this embodiment will be explained with reference to the flowchart shown in FIG.

First, the processing device 2 reads control data via the control data line 8 from the address of the control memory 4 specified by the information lines 6, 7 and 10 (step 2). This read control data indicates the start address of the input/output control processing program, and the microprogram jumps to that address (step 2).

The processing device 2 performs input/output control processing by executing the input/output control program to which it jumps (step ■), and after completing the input/output control processing, sends information indicating the next input/output control state to the information line 6. Step ■) Move to the next process.

〔Effect of the invention〕

As explained above, the present invention provides a control memory circuit in which the start address of an input/output control processing program necessary for data transfer control of a plurality of input/output devices is stored, and a microprogram reads this control memory. Complex input/output control processing can be performed simply by jumping to the address indicated by the data, and microprograms can be created for each input/output control processing without being aware of the input/output control status, allowing program debugging and This has the effect of making it easier to add functions.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the present invention, and FIG. 2 shows a processing flowchart by a processing device in this embodiment. 1... ROM, 2... Processing device, 3.9... Input/output device, 4... Control memory, 5... IO bus 6,
7゜10...Information line, 8...Control data line.

Claims (1)

[Claims] In an input/output control method that performs complex data transfer control using a microprogram for a plurality of input/output devices, the input/output control state of a processing device that executes the microprogram and the input/output control state of each of the input/output devices is provided. A control memory is provided for storing control data for each address determined by the operating state, and the microprogram has an input/output control program having the control data as a leading address, and the processing device reads the control data from the control memory. An input/output control method that operates to read control data, execute the input/output control program specified by the control data, and then set the next input/output control state.