Atmel STK511, User Manual

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STK511 Transmitter Board
STK511 User Guide 5-7
4842B–AVR–10/09
LDI mode,ASK ; TP - Set mode to ASk
RJMP ISRPinLoop ; TP - Exit button ISR
ISRPinS1:
LDI R16,0x50 ; TP - If S1 pressed first set up WDT to 1/4 sec
OUT WDTCR,R16
LDI R16,0x44 ; TP - This will start the timer when sei
OUT WDTCR,R16 ; TP - Then set number of interrupts in 30 sec
LDI WDTcounter, 0x78 ; 0x78=120 - sleep after 0.25x120=30 secs
RJMP ISRPinLoop ; TP - Exit button ISR when button released
ISRPinS2:
LDI R16,0x50 ; TP - If S2 pressed first set up WDT to 8
sec
OUT WDTCR,R16
LDI R16,0x61 ; TP - This will start the timer when sei
OUT WDTCR,R16 ; TP - Then set number of interrupts in 30
sec
LDI WDTcounter, 0x04; 0x04 - sleep after 8x4=32 secs
RJMP ISRPinLoop ; TP - Exit button ISR when button released
ISRPinLoop:
WDR ; TP - Clear watchdog timer
IN R16,PINB ; TP - Check for button release
ANDI R16,0x06 ; TP - If either button still pressed, loop
BRNE ISRPinLoop ; TP - When both buttons released exit ISR
RCALL Debounce ; TP - Add delay for debounce
ISRPinChgEnd:
LDI r16, 0x20
OUT GIFR, r16 ; clear Pin Chg Interrupt Flag
; just caused by releasing switch
SEI ; TP - Enable interrupts
OUT SREG, r31 ; restore Status Register
POP R16 ; TP - All functions must have push and pop
statements!
RETI