e-mail: info@flexputer.de
29/07/02 10:43
The Micro Code ROM (MCROM) is a 1024 x 20 bit ROM(RAM) and contains the micro code instructions.
JP19
Fetch1 Bit18
3 Bit17 16 15
5 Bit14 13 12 11 10
5 Bit9 8 7 6 5
5 Bit4 3 2 1 0
0
ALU Opr
DstReg
SrcBReg
SrcAReg
1
0 - Jump1 - Jump Zero2 - Call3 - Call Z4 - Return5 - finish
Jump Address
6 - Read Mem7 - WriteMem
No of bytes
AddrReg
DataReg
When JP is ‘0’ a register to register operation is executed.
The Fetch Bit (FB) is used to tell the External Memory Unit to fetch the next instruction, even if the current micro code sequence is not finished.
Call and Return are currently not implemented.