UPD63AGS NEC, UPD63AGS Datasheet - Page 43

• Manufacturer Part Number: UPD63AGS
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER FOR INFRARED REMOTE CONTROL TRANSMISSION
• Manufacturer: NEC

9.8 Subroutine Instructions
performs page optimization, it is unnecessary to designate pages. The pages allowed for each product are as
follows.
The program memory consists of pages in steps of 1K (000H to 3FFH). However, as the assembler automatically
CALL addr
RET
PD63 (ROM: 0.5K steps)
PD63A (ROM: 0.75K steps): page 0
PD64 (ROM: 1K steps)
PD6P4B (PROM: 1K steps) : page 0
<1> Instruction code :
<2> Cycle count
<3> Function
<1> Instruction code :
<2> Cycle count
<3> Function
Increments (+1) the stack pointer value and saves the program counter value in the address stack
register. Then, enters the address specified with 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.
: 2
: SP
: 1
: PC
page 0
ASR
PC
SP
a
0 0 1 1 0 1 0 0 1 0
0 1 0 0 0 1 0 0 1 0
9
: page 0
: page 0
a
7
a
6
SP + 1
addr
ASR
SP – 1
a
5
PC
a
0 1 0 0 0 1 0 0 0 1
4
a
8
a
3
a
2
a
1
a
0
; page 1
0 1 0 0 1 1 0 0 0 1
9
to a
0
) into the program counter.
PD63, 63A, 64
43