JPH01171029A - Microprogram controller - Google Patents

Abstract

PURPOSE:To control a data processor for many purposes by selecting control information from 3 types of microprogram control memories and operating the data processor by the information of a microprogram switch register. CONSTITUTION:The control information from 3 types of microprogram control memories 11-13 is selected and a data processor 10 is operated by the information of a microprogram switch register 20. Consequently, since the data processor 10 can be controlled concerning the condition of the data processor 10, the arithmetic resultor the branching from a microprogram main routine to a subroutine, the branching of the microprogram occurs due to the condition on the way of the subroutine, the arithmetic result, etc. Even when the processing after returning from the subroutine to the main routine is different, various processings can be executed by the main routine and control data from the control memory can be changed. Thus, the data processor can be controlled for the many purposes.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an information processing device, and particularly to a microprogram control method thereof.

[Prior Art] In a conventional microprogram control type information processing device, control information is stored in a read-only microprogram or written in advance in a writable microprogram control storage device and read out sequentially. was used to control data processing equipment. Also,
Regarding the use of microprogram subroutines, the main microprogram processing was performed according to an address set in advance in a return address register.

[Problems to be Solved by the Invention] In the conventional microprogram control method described above, the data processing He is operated by the control memory read out using one type of microprogram control memory. The drawback is that it is impossible to change part of the control memory depending on the state or calculation result, or to return to a main routine address other than a preset return address, making it impossible to perform dynamic microprogram control. I had.

[Means for Solving the Problems] The present invention provides a microprogram control type information processing device that includes a writable microprogram control storage device, a read-only microprogram control storage device,
Microprogram return address +9. a device;
It has a readable/writable microprogram switch register that selects any of the control information in these microprogram control storage devices, and the control information from the three types of microprogram control storage devices mentioned above is controlled by the information in the microprogram switch register. The gist is to select and operate the data processing device.

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

The attached figure is a block diagram showing one embodiment of the present invention. In the information processing apparatus shown in the attached figure, the data in the read-only microprogram control storage device 11 or the writable microprogram control storage device 12 is selected by the multiplexer 15 according to the value of the microprogram switch register 20, and data is similarly output from the microprogram main routine. When branching to a subroutine and, conversely, returning to the main routine, the data in the microprogram return address storage device 13 is selected by the multiplexer 15 and set in the microprogram data register 14. The data in the microblock data register 14 is sent to the data processing device 10 via the control bus 110,
Controls the data processing device IO.

Writable microprogram switch register 2
A value of 0 indicates whether the control data from the read-only microprogram storage device 11, the control data from the writable microprogram storage device 12, or the subroutine is used depending on the state of the data processing device 10 or the calculation result. When branching to the main routine and returning to the main routine, it is possible to output control information using the return address from the microprogram return address storage device 13, depending on the user's purpose.

[Effects of the Invention] As explained above, the present invention has three types of microprogram control storage devices, and by selecting one of these according to the value of the microprogram switch register, the state of the data processing device, the result of operation, or the The data processing device can be controlled in relation to branching from the program main routine to subroutines, etc., so when a microprogram branch occurs due to the state in the middle of a subroutine or the result of an operation, and the processing after returning from the subroutine to the main routine is different. However, various processes can be performed at high speed in the main routine. Furthermore, there is an effect that the data processing device can be controlled in many ways by changing the control data from the control memory.

[Brief explanation of the drawing]

The attached figure is a block diagram showing one embodiment of the present invention. 10...Data processing device, 11...Read-only microprogram storage device, 12...Writable microprogram storage device, 13...Microprogram return address storage device, 14... Microprogram data register, 15
...Multiplexer, 16...Multiplexer, 18...Microprogram next address register, 20...Microprogram switch register, 21
...Microprogram return mechanism control circuit. Patent Applicant: NEC Corporation Representative, Patent Attorney: Kiyoshi Kuwai −

Claims (1)

[Claims] In a microprogram control type information processing device,
A writable microprogram control storage device, a read-only microprogram control storage device, a microprogram return address storage device, and a read/write device for selecting any of the control information in these microprogram control storage devices. 1. A microprogram control device comprising a microprogram switch register, and operating a data processing device by selecting control information from the aforementioned three types of microprogram control storage devices based on information in the microprogram switch register.