Intel 8253 - Page 558

XA User Guide 6-158 4/17/98
SUB Rd, #data8
Bytes: 3
Clocks: 3
Operation: (Rd) <-- (Rd) - #data8
Encoding:
byte 3: #data8
SUB Rd, #data16
Bytes: 4
Clocks: 3
Operation: (Rd) <-- (Rd) - #data16
Encoding:
byte 3: upper 8 bits of #data16
byte 4: lower 8 bits of #data16
SUB [Rd], #data8
Bytes: 3
Clocks: 4
Operation: ((WS:Rd)) <-- ((WS:Rd)) - #data8
Encoding:
byte 3: #data8
SUB [Rd], #data16
Bytes: 4
Clocks: 4
Operation: ((WS:Rd)) <-- ((WS:Rd)) - #data16
Encoding:
byte 3: upper 8 bits of #data16
byte 4: lower 8 bits of #data16
1 0 0 1 0 0 0 1 d d d d 0 0 1 0
1 0 0 1 1 0 0 1 d d d d 0 0 1 0
1 0 0 1 0 0 1 0 0 d d d 0 0 1 0
1 0 0 1 1 0 1 0 0 d d d 0 0 1 0