Galactic Electronics Projects

4 bit CPU - Micro-instruction code detail.

Starting at address zero and incrementing by one for each line, four for each instruction.

                                                                            /E      HEX
      LTCH INC  /LD  /INC /DEC LTCH /WR  LTCH                /RST LTCH /RD  INS  /E ROM
      INS  PC   ACC  ACC  ACC  REG  REG  FLAG JMPL JMPE JMPG PC   OUT  REG  DATA IN 0  1 

FETCH 1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      0    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  7F FF
      1    0    1    1    1    1    1    1    1    1    1    1    1    1    1    1  BF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

LIT   1    1    1    1    1    1    1    1    1    1    1    1    1    1    0    1  FF FD
      1    1    0    1    1    1    1    1    1    1    1    1    1    1    1    1  DF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    0    1  FF FD

LOAD  1    1    1    1    1    1    1    1    1    1    1    1    1    0    1    1  FF FB
      1    1    0    1    1    1    1    1    1    1    1    1    1    1    1    1  DF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    0    1    1  FF FB

STORE 1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    0    1    1    1    1    1    1    1    1    1  FD FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

INC   1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    0    1    1    1    1    1    1    1    1    1    1    1    1  EF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

DEC   1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF  
      1    1    1    1    0    1    1    1    1    1    1    1    1    1    1    1  F7 FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

REG   1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    0    1    1    1    1    1    1    1    1    1    1  FB FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

CMPL  1    1    1    1    1    1    1    1    1    1    1    1    1    1    0    1  FF FD
      1    1    1    1    1    1    1    0    1    1    1    1    1    1    1    1  FE FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    0    1  FF FD

CMPR  1    1    1    1    1    1    1    1    1    1    1    1    1    0    1    1  FF FB
      1    1    1    1    1    1    1    0    1    1    1    1    1    1    1    1  FE FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    0    1    1  FF FB

RST   1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    0    1    1    1    1  FF EF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

JUMPL 1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    0    1    1    1    1    1    1    1  FF 7F
      1    1    1    1    1    1    1    1    1    1    1    0    1    1    1    1  FF EF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

JUMPE 1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    0    1    1    1    1    1    1  FF BF
      1    1    1    1    1    1    1    1    1    1    1    0    1    1    1    1  FF EF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

JUMPG 1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    0    1    1    1    1    1  FF DF
      1    1    1    1    1    1    1    1    1    1    1    0    1    1    1    1  FF EF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

IN    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    0  FF FE
      1    1    0    1    1    1    1    1    1    1    1    1    1    1    1    1  DF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    0  FF FE

OUT   1    1    1    1    1    1    1    1    1    1    1    1    1    0    1    1  FF FB
      1    1    1    1    1    1    1    1    1    1    1    1    0    1    1    1  FF F7
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    0    1    1  FF FB

NOP   1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF
      1    1    1    1    1    1    1    1    1    1    1    1    1    1    1    1  FF FF

Send questions and comments to WireHead@GalacticElectronics.com

(c) Jon Qualey, December 2006

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