Rainbow Electronics AT89C2051 - Manual (Page 11)

Microcontroller
5-57
Table 7. Miscellaneous Instructions
Note: 1. ALT obtains the remainder after DIV and obtains the high word after a multiply. This instruction must be executed immedi-
ately after the MUL or DIV.
Name Description
CLR Zero ACC
COM Complement ACC (ACC = ACC XOR FFFF)
NEG Negate ACC (ACC = 0 - ACC)
NOT ACC = 1 if ACC was 0, else ACC = 0
INC Increment ACC
DEC Decrement ACC
TAI Copy ACC to INDEX
TIA Copy INDEX to ACC
ADAI Add ACC to INDEX
ALT Get alternate result from MUL/DIV
OUT Output byte in ACC to PORT
IN Read byte from PORT
SYS System interface function