INSTRUCTION DESCRIPTIONS
MOTOROLA INSTRUCTION SET DETAILS A - 185
Class II Instruction Format:
( . . . . . ) A➞X:ea X0➞A
( . . . . . ) B➞X:ea X0➞B
Opcode:
Instruction Fields:
ea=6-bit Effective Address=MMMRRR
Effective
Addressing Mode M M M R R R
(Rn)-Nn 0 0 0 r r r
(Rn)+Nn 0 0 1 r r r
(Rn)- 0 1 0 r r r
(Rn)+ 0 1 1 r r r
(Rn) 1 0 0 r r r
(Rn+Nn) 1 0 1 r r r
-(Rn) 1 1 1 r r r
where “rrr” refers to an address register R0–R7
SD D
S D S/L Sign Ext Zero d MOVE Opcode
X0 no N/A N/A 0 A➞X:ea X0➞A
Y0 no N/A N/A 1 B➞X:ea X0➞B
A yes A2 A0
B yes B2 B0
Timing: mv oscillator clock cycles
Memory: mv program words
23 16 15 8 7 0
OPTIONAL EFFECTIVE ADDRESS EXTENSION
0 0 0 0 1 0 0 d 0 0 M M M R R R INSTRUCTION OPCODE
X:R X Memory and Register Data Move X:R