IBM 5150 Hardware Reference Manual page 283

SBB = Subtract with borrow
Reg./memory and register to either
1 0 0 0 1 1 0 d w 1 mod reg rIm
Immediate from register/memory
11 0 0 0 0 0 s w 1 mod 0 1 1 rIm
data data if s:w=Ol
Immediate from accumulator
10001110w data
data if w=l
DEC = Decrement
Register/memory
11111111w
mod 0 0 1 rIm
Registe,·
1 0 1 0 0 1 reg 1
NEG = Change sign
11111011w
mod 0 1 1 rIm
CMP = Compare
Register/memory and register
1 0 0 1 1 1 0 d w 1 mod reg rIm
Immediate with register/memory
11 0 0 0 0 0 s w 1 mod 1 1 1
rim data data if s:w=Ol
Immediate with accumulator
1 0 0 1 1 1 lOw 1 data
data if w=l
AAS = ASC" adjust for subtract
1001111111
DAS = Decimal adjust for subtract
1001011111
MU
L
= Multiply (unsigned)
11 1 1 1 0 1 1 w 1 mod 1 0 0
rim
IMU
L
= Integer multiply (signed)
11 1 1 1 0 1 1 w 1 mod 1 0 1
rim
1
B-8