st72324bk STMicroelectronics, st72324bk Datasheet - Page 164

• Manufacturer Part Number: st72324bk
• Description: 3 V/5 V Range 8-bit Mcu With 4/8 Kbyte Rom, 10-bit Adc, Four Timers And Spi
• Manufacturer: STMicroelectronics

Known limitations
164/167
Case 2: Writing to PxOR or PxDDR with global interrupts disabled
SIM
LD A,PFDR
AND A,#$02
LD X,A
LD A,#$90
LD PFDDR,A
LD A,#$ff
LD PFOR,A
LD A,PFDR
AND A,#$02
LD Y,A
LD A,X
cp A,#$02
jrne OUT
TNZ Y
jrne OUT
LD A,#$01
LD sema,A
RIM
LD A,sema
CP A,#$01
jrne OUT
call call_routine
RIM
OUT:
JP while_loop
.call_routine
PUSH A
PUSH X
PUSH CC
.ext1_rt
LD A,#$00
LD sema,A
IRET
; set the interrupt mask
; store the level before writing to PxOR/PxDDR
; Write into PFDDR
; Write to PFOR
; store the level after writing to PxOR/PxDDR
; check for falling edge
; set the semaphore to '1' if edge is detected
; reset the interrupt mask
; check the semaphore status
; call the interrupt routine
RIM
; entry to call_routine
; entry to interrupt routine
ST72323 ST72323L