COP87LXXCJ Datasheet, PDF (22/28 Pages) National Semiconductor (TI) – 8-Bit CMOS OTP Microcontrollers with 4k or 32k Memory and Comparator

Instruction Execution Time
Most instructions are single byte (with immediate addressing
mode instruction taking two bytes).
Most single instructions take one cycle time to execute.
Skipped instructions require x number of cycles to be
skipped, where x equals the number of bytes in the skipped
instruction opcode.
See the BYTES and CYCLES per INSTRUCTION table for
details.
BYTES and CYCLES per
INSTRUCTION
The following table shows the number of bytes and cycles for
each instruction in the format of byte/cycle.
Arithmetic Instructions (Bytes/Cycles)
ADD
ADC
SUBC
AND
OR
XOR
IFEQ
IFGT
IFBNE
DRSZ
SBIT
RBIT
IFBIT
[B]
Direct
Immed.
1/1
3/4
2/2
1/1
3/4
2/2
1/1
3/4
2/2
1/1
3/4
2/2
1/1
3/4
2/2
1/1
3/4
2/2
1/1
3/4
2/2
1/1
3/4
2/2
1/1
1/3
1/1
3/4
1/1
3/4
1/1
3/4
Memory Transfer Instructions (Bytes/Cycles)
Register
Indirect
[B] [X]
X A,*
1/1 1/3
LD A,*
1/1 1/3
LD B,Imm
LD B,Imm
LD Mem,Imm
LD Reg,Imm
* = > Memory location addressed by B or X or directly.
Direct
2/3
2/3
3/3
Immed.
2/2
1/1
2/3
2/3
Register Indirect
Auto Incr & Decr
[B+, B−]
[X+, X−]
1/2
1/3
1/2
1/3
2/2
(If B < 16)
(If B > 15)
Instructions Using A & C
Instructions
CLRA
INCA
DECA
LAID
DCORA
RRCA
SWAPA
SC
RC
IFC
IFNC
Bytes/Cycles
1/1
1/1
1/1
1/3
1/1
1/1
1/1
1/1
1/1
1/1
1/1
Transfer of Control Instructions
Instructions
JMPL
JMP
JP
JSRL
JSR
JID
RET
RETSK
RETI
INTR
NOP
Bytes/Cycles
3/4
2/3
1/3
3/5
2/5
1/3
1/5
1/5
1/5
1/7
1/1
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