AN2839 Freescale Semiconductor / Motorola, AN2839 Datasheet - Page 16

• Manufacturer Part Number: AN2839
• Description: Implementing a Lamp Dimmer with an HC908Q Family MCU
• Manufacturer: Freescale Semiconductor / Motorola

Software Description
DecTimer:
EscapeDec:
Delay:
Xloop:
Skip:
;*******************************************************************************************
;* Main Init
;* This is the point where code starts executing after a RESET.
;*******************************************************************************************
main:
16
lda
sta
lda
sta
bra
decx
cpx
blo
lda
sta
lda
sta
bra
ldx
lda
sta
lda
sta
bra
lda
brn
brn
dbnza Xloop
rts
mov
mov
mov
bset
bset
bset
clr
clr
clrh
ldx
jsr
cli
MSBTimer,x
TMODH
LSBTimer,x
TMODL
Skip
#DecTcomp
EscapeDec
MSBTimer,x
TMODH
LSBTimer,x
TMODL
Skip
#DecTcomp
MSBTimer,x
TMODH
LSBTimer,x
TMODL
Skip
#Delval
*
*
#initCfg1,CONFIG1 ;Set config1 register
#initCfg2,CONFIG2 ;set MCU to internal oscillator, IRQ enabled
#InitDDRA,DDRA ;PTA0 -> Zero Crossing detection
DDRA1,DDRA
PTAPUE4,PTAPUE
PTAPUE5,PTAPUE
Counter1
Counter2
#Xval
InitTimer
Implementing a Lamp Dimmer with an HC908Q Family MCU, Rev. 0
;(LVI and COP disabled)
;PTA1 -> Pulses on Thyristor gate
;PTA2 as IRQb -> Turns on dimmer
;PTA3 as RSTb -> Turns on 1-minute timer
;PTA4 -> Dec. lamp brightness
;PTA5 -> Inc. lamp brightness
;Goes config Timer
;Allow interrupts to happen
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