JPS61267833A - Instruction set forming system for microcomputer - Google Patents

Abstract

PURPOSE:To improve the using efficiency of a memory and to increase the processing speed of the memory by executing selectively either one of plural instruction sets through execution of a specific instruction or by means of an external event. CONSTITUTION:When a microcomputer executes an instruction 30 and then an instruction 31, another instruction set is selected since the instruction 31 is used for selection of instruction sets. Thus the execution of the next instruction is started and carried out continuously with an instruction 40 belonging to another instruction set. If an interruption 50 is produced during execution of the next instruction 41, the original instruction set is selected. Then the execution of instructions is started at an instruction 32 belonging to the selected original instruction and carried out continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an instruction set configuration method for a microcomputer.

[Summary of the invention]

The present invention is an instruction set configuration method for a microcomputer in which the instruction set is dynamically changed in response to a specific instruction of the microcomputer or an event such as an external interrupt, thereby achieving higher memory usage efficiency and processing speed. This allows for improvements to be achieved.

[Prior art]

In conventional microcomputers, only one instruction set is provided for each model.

[Problems and objectives to be solved by the invention] If we try to construct an optimal instruction set for this nineteenth number of applications, the number of instructions will increase by one, and a large number of code areas will be required to map these instructions. Ta.

Regarding mapping, for example, 1 byte is allocated to instructions that are used frequently on average, and 2 bytes are allocated to other instructions, making it difficult to construct an instruction set that is optimized for many applications. Ta.

On the other hand, on the application side, it is rare that all instructions are used at the same time, such as comparison and conditional branching in a control system, addition and multiplication in a formula processing system, and index reference and data in a data processing system. They often used instructions that belonged to a specific group, such as transfer.

For this reason, as mentioned above, with conventional instruction sets, depending on the application, the number of bytes is large, and therefore instructions that take a long time to process may be used frequently, resulting in insufficient memory usage efficiency and processing speed. Ta.

[Means to solve the problem]

In order to solve the above-mentioned problems, the microcomputer according to the present invention is equipped with a plurality of instruction controllers, and the plurality of instruction sets can be changed by executing a specific instruction in the instructions or by an external event. The feature is that either one can be executed selectively.

[Effect]

Assume that one instruction set is selected from a plurality of instruction sets, and the microcomputer is executing under that instruction set.

In this state, if the microcomputer executes the instruction set selection instruction, execution of the instructions continues using the next instruction or the instruction set specified by the instruction set selection instruction.

Furthermore, if the instruction set selection instruction is executed during the original execution of the specified instruction set, the execution continues under the new instruction set in the same way as above.

In this way, any other instruction set can be selected from any instruction set. Further, when an external event such as an interrupt occurs, a new instruction set is selected as necessary, and execution is performed based on the selected instruction set.

〔Example〕

FIG. 1 is an example of the invention in which a microcomputer is executed using any of the 10.20 instruction sets. FIG. 2 is a diagram showing the instruction stream of the microcomputer in FIG. Each of the instructions in FIG. 1 belongs to the instruction set 20 on the right side of FIG. Now a microcomputer man,
Assume that instruction 3o is executed and then instruction 31 is executed. At this time, since 31 is an instruction set selection instruction, the instruction set 20 is selected, and the next instruction is executed from the instructions 40 belonging to the instruction set 20. Furthermore, the instructions 41 and 41 are executed, but an interrupt 50 occurs during the execution of the instruction 41. Therefore, the instruction set 10 is selected, and the execution of the Mff 104y instruction is performed using instructions belonging to the selected instruction set 10. Continued from 32.

〔effect〕

As mentioned above, by providing multiple instruction sets that are optimal for the anticipated application,
This has the effect of improving memory usage efficiency and processing speed.

[Brief explanation of the drawing]

Figure 1 shows the origin of the instruction manual (Jilt diagram) of the present invention. 10.20 are independent instruction sets in the same microcomputer, and are depicted as an instruction map. 1.1t21 is a set of dedicated instructions that do not exist in common in 10.20, and 12.22 is a set of dedicated instructions that do not exist in common in 10.
This is a set of instructions common to 20. Further, 15.25 are instructions for selecting the instruction set of 20.10. FIG. 2 is a diagram showing an instruction stream for explaining FIG. 1. 30 to 35 are instructions belonging to instruction set 10;
．． 41 is an instruction belonging to the instruction set 20. In particular, 31 is an instruction for selecting the instruction set 20, which corresponds to FIG. 13. Further, 50 means an interrupt signal. 10.20...Instruction set 11.21
...Special instructions 12.22...Common instructions 13.23...Instruction set selection instructions 30.32, 33...Instruction set 10
Instruction 31 belonging to instruction set 10 Instruction set selection instruction 40 belonging to instruction set 10.41... Instruction 50 belonging to instruction set 20... Interrupt signal acid top

Claims (1)

[Claims] It has a plurality of instruction sets, any one of which is selected, and the selected instruction set is activated by executing a specific instruction in the selected instruction set or by an external event. One of all instruction sets including the instruction set is selected and replaces some or all of the selected instruction set, the selected instruction set is deselected, and the replaced instruction set is newly selected. A microcomputer instruction set configuration method characterized by an instruction set.