JPS5925251B2 - Creation method for arithmetic control signals in microprogram-controlled electronic computers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for creating arithmetic control signals in a microprogram-controlled electronic computer.

Conventionally, as a method for creating arithmetic control signals in an electronic computer under this type of microprogram control, as shown in FIG. A method is known in which the contents of the microinstruction register 2 are latched and the contents of the microinstruction register 2 are decoded by a decoder 3 to create a control signal necessary for executing an operation of an electronic computer.

However, according to such a conventional method, when arithmetic control data is designated by the decoded output 4 of the decoder 3 and a control signal is created based on this content, the decoded output 4n of the decoder 3 is In such a case, it is necessary to enable the secondary decoder 6 and decode the contents of the register 5 that stores the calculation control data using the secondary decoder 6 to obtain the same calculation control signal.
When the decode output 4a of the decoder 3 and the decode output 7a of the secondary decoder 6 are the same type of arithmetic control signal, for example, a data write command to the same arithmetic register, the logical sum of the decode output 4a and the decode output Ta is used. It requires an OR circuit 8 that takes
At the same time, the delay time from latching the read data of the control storage unit 1 to the microinstruction register 2 to obtaining the arithmetic control signal becomes large, making it impossible to apply it to electronic computers that require high-speed arithmetic cycles. There was a drawback. Therefore, an object of the present invention is to input either the read data of the control memory unit or the arithmetic control data specified by the read data to the microinstruction register that latches the read data of the control memory unit. By configuring it so that it can be set, the hardware configuration required for creating arithmetic control signals is simplified, and the present invention aims to provide a method for creating arithmetic control signals that is applicable to electronic computers that require high-speed arithmetic cycles. It is something.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3 of the accompanying drawings.

In FIG. 2, the present invention includes a control storage unit 11 that stores a microprogram, a register 12 that stores arithmetic control data specified by read data of the control storage unit 11, and a register 12 that stores arithmetic control data specified by read data of the control storage unit 11. A code detection circuit 13 generates a signal only when the data is a code instructing indirect designation;
The selection circuit 14 which switches according to the output of 3 and the selection circuit 1
4, and a decoder 16 that decodes the contents of the microinstruction register 15 and generates an arithmetic control signal.

In this configuration, if the read data 17 of the control storage unit 11 does not match the code instructing indirect designation of the arithmetic control signal, the output 1 of the code detection circuit 13
8 is at a low level, read data 17 is selected as the output of the selection circuit 14, and the microinstruction register 15
is set to

The contents of this microinstruction register 15 are then decoded by a decoder 16 to generate an arithmetic control signal 19. Equivalently, the read data 17 is decoded, and the arithmetic control signal 19 is generated by the control memory. It will be generated according to the microprogram stored in the unit 11. Further, when the read data 17 of the control storage unit 11 matches a code that instructs indirect designation of the arithmetic control signal, the output 18 of the code detection circuit 13 becomes high level, and the output of the selection circuit 14 becomes a register. 12, and the contents of the register 12 indirectly specified by the read data 17 are set in the microinstruction register 15.

The contents of this microinstruction register 15 are decoded by the decoder 16, and an arithmetic control signal 19 is generated to control the arithmetic operation. That is, the arithmetic control in this case is not executed according to the microprogram stored in the control storage unit 11, but according to the contents of the register 12 indirectly specified by the microprogram. Next, FIG. 3 is a diagram for explaining the operation of this invention by giving an example. A value is given to each.

To simplify the explanation, it is assumed that the word length of the read data 17 of the control storage unit 11, the register 12, and the microinstruction register 15 is 2 bits each, and the code of the read data 17 is ``11''. The operation of the present invention will be explained on the assumption that the output 18 of the code detection circuit 13 goes to the low level when Data C indicates the pattern of the register 12 that is indirectly specified, and data D indicates the contents set in the microinstruction register 15. 17
is a code other than '11'', the data B
As shown in FIG.
5, the read data 17 is set as is, no matter what the contents of the register 12 are.

On the other hand, the read data 17 shown in the data A is
1I, the output 18 of the code detection circuit 13 becomes high level as shown in the data B, and the selection circuit 14 switches to the register 12. Therefore, the microinstruction register 15 shown in the data D has the following information. The contents of register 12 will be set. However, as a result of the arithmetic control data being set in the microinstruction register 15 in this way, the contents of the register 12 become 00!, as shown in the article column of the same chart. If I, the read data 17 is '001', if the contents of the register 12 are '01'', the read data 17 is '01'', and if the contents of the register 12 are '10'', the read data 17 is '10''. In each case, the same arithmetic control signal 19 is generated from the decoder 16 to control the arithmetic operation of the computer, and if the contents of the register 12 are ``11'', it cannot be executed with the read data 17. New calculation control can be executed.

In the above description, it goes without saying that by providing a plurality of registers 12, code detection circuits 13, and selection circuits 14, the number of arithmetic control data that can be indirectly designated can be increased.

As described in detail above, according to the present invention, read data of the control storage unit,
Alternatively, since either one of the arithmetic control data indirectly specified by this read data can be set, it is possible to simplify the creation of this kind of arithmetic control signal, and it also eliminates the need for high-speed arithmetic cycles. It is highly effective when applied to electronic computers.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional calculation control signal creation method, FIG. 2 is a block diagram showing an embodiment of the calculation control signal creation method according to the present invention, and FIG. 3 is a block diagram showing an example of the operation of the invention. This is a chart showing. 11... Control storage unit, 12...
Register, 13... Code detection circuit, 14...
... Selection circuit, 15 ... Microinstruction register, 16 ... Decoder, 17 ... Control storage unit read data, 18 ... Code detection Circuit output, 19...Arithmetic control signal.

Claims (1)

[Claims] 1. In a microprogram-controlled electronic computer, when a register for storing arithmetic control data is specified by an arithmetic control field in read data of a control storage unit, the contents of the arithmetic control field in the read data of the control storage unit A micro-instruction register is provided which switches and latches the contents of the register storing the arithmetic control data, and the contents latched in the micro-instruction register are decoded to generate the arithmetic control signal. Method for creating calculation control signals.