9/18 bit Cpu Dec 7,2008

This is a 9/18 computer about 1976 ish. This one will have a
a real front panel / switches /leds and single instruction step
operation. CPU,64Kb memory+Boot Rom and a uart will be standard.
The cpu is two 128 cell CPLD's and one 128 cell CPLD for the control logic.
The sample  48 pin DIP production date is expected to be April 1,1977
with a 5 MHZ clock. Instruction times are 1.6 us to 4.0 us long.

Registers  C,A,X,S    C is A with carry
Index  01,B2,X,S       
1: ~I is word #,I is # short
2:  is direct page reg - 4 kb page size .
 

8 7 6   5 4 3   2 1 .  9 8 7   6 5 4   3 2 1
_ _ _   _ _ _   _ _ _  _ _ _   _ _ _   _ _ _ 
. OP .  I .AC.  B .IX. # # #   # # #   # # #  opcode normal - immedate char
# # #   # # #   # # #  # # #   # # #   # # #  immedate word - special 


OP: st/ctrl,scc/lea/shift,add/c,sub/c,and/jms/inc*,or/jmp/dec*,xor/jz*/inc2*,ld/jnz*/dec2*
I:  Indirect bit
B:  Byte sized operand
* direct mode only

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