UPD6P8 NEC [NEC], UPD6P8 Datasheet - Page 54

• Manufacturer Part Number: UPD6P8
• Description: MOS INTEGRATED CIRCUIT 4-BIT SINGLE-CHIP MICROCONTROLLER FOR INFRARED REMOTE CONTROL TRANSMISSION
• Manufacturer: NEC [NEC]

10.8 Subroutine Instructions
performs page optimization, it is unnecessary to designate pages. The pages allowed for each product are as
follows.
54
JNF addr
The program memory consists of pages in steps of 1K (000H to 3FFH). However, as the assembler automatically
µ PD6P8, 6P8A, 6P8B (ROM: 2K steps): Pages 0, 1
CALL addr
RET
<1> Instruction code:
<2> Cycle count:
<3> Function:
<1> Instruction code:
<2> Cycle count:
<3> Function:
<1> Instruction code:
<2> Cycle count:
<3> Function:
If the status flag F is cleared (to 0), a jump is made to the address specified by addr (a
Increments (+1) the stack pointer value and saves the program counter value in the address stack
register. Then, enters the address specified by the operand addr (a
If a carry is generated when the stack pointer value is incremented (+1), an internal reset takes effect.
Restores the value saved in the address stack register to the program counter. Then, decrements
(–1) the stack pointer.
If a borrow is generated when the stack pointer value is decremented (–1), an internal reset takes effect.
Page 0
Page 2
1
if F = 0 PC ← addr
else PC ← PC + 2
Page 0
Page 2
2
SP ← SP + 1
ASR ← PC
PC ← addr
1
PC ← ASR
SP ← SP – 1
a
a
0 0 1 1 0 1 0 0 1 0
0 1 0 0 0 1 0 0 1 0
9
9
a
a
7
7
a
a
6
6
a
a
5
5
a
a
0 1 1 1 1 1 0 0 0 1
0 1 1 1 1 1 0 1 0 0
0 1 0 0 0 1 0 0 0 1
0 1 0 0 0 1 0 1 0 0
4
4
a
a
8
8
Data Sheet U17848EJ3V0DS
a
a
3
3
a
a
2
2
a
a
1
1
a
a
0
0
; page 1
; page 3
; page 1
; page 3
1 0 0 0 1 1 0 0 0 1
1 0 0 0 1 1 0 1 0 0
0 1 0 0 1 1 0 0 0 1
0 1 0 0 1 1 0 1 0 0
9
to a
0
µ PD6P8, 6P8A, 6P8B
) into the program counter.
9
to a
0
).