Maxim Integrated DS4830A Optical Microcontroller User Manual
Page 217

DS4830A User’s Guide
217
NEG
Negate Accumulator
Description:
Performs a negation (two’s complement) of the active accumulator and returns the result
back to the active accumulator.
Status Flags:
S, Z
Operation:
Acc
~Acc + 1
Encoding:
15
0
1000
1010
1001
1010
Example(s):
; Acc = FEEDh, S=1, Z=0
NEG
; Acc = 0113h, S=0, Z=0
OR src
Logical OR
Description:
Performs a logical-OR between the active accumulator (Acc or A[AP]) and the specified src
data. For the complete list of src specifiers, reference the MOVE instruction. Because the
source is limited to 8 bits, the PFX[n] register is used to supply the high-byte of data for
16 bit sources.
Status Flags:
S, Z
Operation:
Acc
Acc OR src
Encoding:
15
0
f010
1010
ssss
ssss
Example(s):
; Acc = 2345h for each example
OR A[3]
; A[3]= 0F0Fh
Acc = 2F4Fh
OR #1133h
; MOVE PFX[0], #11h (smart-prefixing)
; OR #33h
Acc = 3377h
Special Notes:
The active accumulator (Acc) is not allowed as the src for this operation.
OR Acc. Logical OR Carry Flag with Accumulator Bit
Description:
Performs a logical-OR between the Carry (C) status flag and a specified bit of the active
accumulator (Acc.) and returns the result to the Carry.
Status Flags:
C
Operation:
C
C OR Acc.
Encoding:
15
0
1010
1010
bbbb
1010
Example(s):
; Acc = 2345h, C=0 at start
OR Acc.1
; Acc.1=0
C=0
OR Acc.2
; Acc.2=1
C=1