NEC PD754144 User Manual page 226

<Program example>
BTAND4: SKTCLR
BR
SKT
BR
SET1
WAIT: SKT
BR
SKT
BR
MOV
MOV
[EI
RETI
PDOWN: MOV
MOV
[DI
SETHLT: HALT
NOP
RETI
VSUBBT: CLR1
BR
226
CHAPTER 8 STANDBY FUNCTION
IRQ0 ; INT0 = 1?
VSUBBT ; NO
PORT6.1 ; P61 = 1?
PDOWN ; Power down
BTM.3 ; Starts BT
IRQBT ; Waits for 175 ms
WAIT
PORT6.1
PDOWN
A, #0011B ; High-speed mode
PCC, A
; IEn ← 1
IEn]
A, #0 ; Lowest-speed mode
PCC, A
; IEn ← 0
IEn]
Keeps 46 machine cycles
; HALT mode
IRQBT
Processing during intermittent operation
SETHLT
User's Manual U10676EJ3V0UM