TSC80251 TEMIC [TEMIC Semiconductors], TSC80251 Datasheet - Page 98

• Manufacturer Part Number: TSC80251
• Manufacturer: TEMIC [TEMIC Semiconductors]

Rev. C – May 7, 1999
CJNE <dest>,<src>,rel
Function:
Compare and jump if not equal.
Description:
Compares the magnitudes of the first two operands and branches if their values are not equal. The branch destination
is computed by adding the signed relative displacement in the last instruction byte to the PC, after incrementing the
PC to the start of the next instruction. If the unsigned integer value of <dest–byte> is less than the unsigned integer
value of <src–byte>, the CY flag is set. Neither operand is affected.
The first two operands allow four addressing mode combinations: the accumulator may be compared with any directly
addressed byte or immediate data and any indirect RAM location or working register can be compared with an
immediate constant.
Example :
The accumulator contains 34h and R7 contains 56h. After executing the first instruction in the sequence
the CY flag is set and program execution continues at label NOT_EQ. By testing the CY flag, this instruction
determines whether R7 is greater or less than 60h.
If the data being presented to Port 1 is also 34h, then executing the instruction, WAIT: CJNE A,P1,WAIT clears the
CY flag and continues with the next instruction in the sequence, since the accumulator does equal the data read from
Port 1. (If some other value was being input on Port 1, the program loops at this point until the Port 1 data changes to
34h.)
CJNE A,#data,rel
[Encoding]
FLAGS :
Hex Code in:
Binary Mode = [Encoding]
Source Mode = [Encoding]
B 4
NOT_EQ:
CY
3
immed data
CJNE R7,#60h,NOT_EQ ;R7 = 60h ; . . .
JC
AC
_
REQ_LOW
;R7 > 60h
; . . .
rel addr
; IF R7 < 60h
. . .
OV
_
Operation:
(PC)
IF [(A)
THEN
IF [(A) < #data]
THEN
ELSE
(PC)
(CY)
(CY)
(PC) + 3
#data]
(PC) + relative offset
1
0
. . .
N
3
TSC80251
Z
3
5.53