JPS6371731A - Microprogram controller - Google Patents

Abstract

PURPOSE:To reduce the number of storage elements in a horizontal direction by providing a means which selects whether the micro instruction code read out from a control memory device should be set to a micro instruction register or the output from a serial converting means should be set to the micro instruction register. CONSTITUTION:A micro instruction code 7 read out from the control memory device 1 is converted to a serial converting circuit 2 to generate a serial output signal 8 where bits are arranged in order from a least significant bit. In an input selecting signal generating part 6, the micro instruction code 7 is selected by an input selecting signal 10 generated in the form of division of the address space on the control memory device or a flag register which can be set and reset by a micro instruction. When all of 16 bits are set by the same clock and the serial output signal 8 is selected, the shift function of a micro instruction register 4 is used to store every one bit in the register 4 by one clock and the micro instruction code is stored there by 16 clocks, and the micro instruction is converted to a control signal of each part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a microprogram control device, and more particularly to a microprogram control device that reads and controls microinstructions.

[Conventional technology]

Conventionally, this type of microprogram control device has been operated by directly setting a microinstruction register read from a control storage device.

[Problem that the invention seeks to solve]

The conventional micro program control device mentioned above only uses a method of setting the parallel output from the control storage device to the microinstruction register, so it is necessary to configure the control storage device by using storage elements with different access times. Even in this case, the number of pixels in the horizontal direction must be the same, and the number of storage elements in the horizontal direction cannot be reduced.

[Means for solving problems]

The micro-program control device of the present invention includes a control storage device for storing micro-programs, a micro-instruction register having a shift function, and a serial conversion means for expanding and outputting micro-instruction codes one bit at a time. and means for dynamically selecting either parallel output from the control storage device or serial output from the serial conversion means and setting it in the microinstruction register.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In FIG. 1, this embodiment includes a control storage device 1 that accommodates a microprogram and reads out a microinstruction code 7; a serial conversion circuit 2 that converts into a serial output signal 8; an input selection circuit 3 that selects the microinstruction code 7 and the microinstruction code 8 of the serial output signal; and an input selection signal 10 that controls the input selection circuit 3.
an input selection signal generation unit 6 that generates the microinstruction code 2 or 8, a microinstruction register 4 that holds the microinstruction code 2 or 8, and a microinstruction decoder 5 that decodes the microinstruction code.
including.

FIG. 2 specifically shows the configuration of the microinstruction register 4 and input selection circuit 3 of this embodiment. In FIG. 2, the micro-instruction register 4 and the input selection circuit 3 are configured for each flip/instruction register 4, which has a width of 16 bits, for example.
It is comprised of flops (F/F) 27-42 and selectors 11-26 for input selection of each F/F. First, the operation around the microinstruction register will be explained with reference to FIG.

The microinstruction register in one embodiment of the present invention is 1
It is composed of six flip-flops 27 to 42, and the inputs of each flip-flop except the highest-order flip-flop 27 are input to each bit of the microinstruction code 7 from the control storage device depending on the selection signal 10. or the output of the flip-flop in the previous stage (on the left side of the figure).

The input selector 11 of the most significant flip-flop 27 selects either the most significant microinstruction code 7 and 11 or the serial conversion output signal 8 shown in FIG. 1, depending on the selection signal 10. With this configuration, the microinstruction register 4 is
According to the selection signal 10, the microinstruction code read from the control storage device 1 is accommodated in 16 bits at the same time, or the output signal of the serial conversion circuit is not inserted in the most significant bit, and the shift function is shifted to the right one bit at a time. It is possible to choose whether to use

The overall operation will be explained with reference to FIG. 1 again.

The microinstruction code 7 read from the control storage device 1 is used by the serial conversion circuit 2 to generate a serial output signal 8 in which each bit is sequentially arranged starting from the least significant bit.

The input selection signal generation section 6 generates the input selection signal 10 to be input to the microinstruction register 4 in one of the following formats.

■ Division of the address space on the control storage device ■ Flag register that can be set and reset by microinstructions When microinstruction code 7 is selected by this input selection signal 10, all 16 bits are set at the same clock. When the serial output signal 8 is selected, the shift function of the microinstruction register 4 is used to
The microinstruction code is stored in the microinstruction register 4 bit by bit in 16 clocks. The microinstructions stored in the microinstruction register 4 are sent to the microinstruction decoder 5.
is converted into control signals for each part.

〔Effect of the invention〕

As explained above, the present invention provides a microinstruction register having a shift I function, a microinstruction code serial conversion means, and a shift function by directly setting the microinstruction code read from the control storage device or via the serial conversion means. By having a means for selecting whether to use or set the control memory, it is possible to configure the control memory device using memory elements with different performances. A low-speed, low-cost memory element for a program capable of low-speed processing can be used by loading the program into a microinstruction register using a shift function. Furthermore, if the present invention is adopted when the number of bits in the horizontal direction of the microinstruction code is large, the memory element is prepared for the number of bits in the horizontal direction because the area where the shift function is used is set in the microinstruction register one bit at a time after serial conversion. There is no need to do this, and the number of storage elements in the horizontal direction can be greatly reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a detailed diagram showing a microinstruction register and an input selection circuit. DESCRIPTION OF SYMBOLS 1... Control storage device, 2... Micro instruction code serial conversion circuit, 3... Micro instruction register input selection circuit, 4... Micro instruction register, 5... Micro instruction decoder, 6... Input selection signal generation section, 7.
...Micro instruction code, 8...Serial conversion output,
9... Microinstruction register input, 10... Input selection signal, 11-26... Clip-flop group forming the micro-instruction register, 27-42... Input selection Sawada selector of each flip-flop. Figure 1 Figure 2

Claims (1)

[Claims] a control storage device for storing microprograms;
a microinstruction register with a shift function; a serial conversion means for expanding the microinstruction code bit by bit; and a microinstruction code read from the control storage device to be set in the microinstruction register or read from the serial conversion means and means for selecting whether to set an output in a microinstruction register using a shift function.