second test pcint0 implementation

diff --git a/foo.S b/foo.S
index 0e3f727fbdffbd3e4c02c0af5611bdfab36c247c..b905a5f170e8bd2ddcbc79a9298157590e425809 100644 (file)
--- a/foo.S
+++ b/foo.S
@@ -50,7 +50,7 @@ FLASHM = 0x4000
        RJMP    main
 .org 0x0004 ; PCINT0 interrupt
        CBI     PCICR, 0 ; disable interrupt
        RJMP    main
 .org 0x0004 ; PCINT0 interrupt
        CBI     PCICR, 0 ; disable interrupt

-       RJMP    pcint_handler
+       RJMP    wakeup

 .org 0x0008 ; TIM0_OVF interrupt
        RJMP    sample
 
 .org 0x0008 ; TIM0_OVF interrupt
        RJMP    sample
 


@@ -194,9 +194,46 @@ main: ; setup routine
        #undef zero
 
 loop:
        #undef zero
 
 loop:

-       SLEEP ; wait for interrupt
+       CPI     i2, 0x78>>5 ; 16m23 -- one loop
+;TODO^: s/>>5//
+       BREQ    halt
+
+       SLEEP ; wait for interrupt -- XXX: does not work, since we forgot to set sleep_enable bit!

        RJMP    loop
 
        RJMP    loop
 

+halt:
+       CLR     i2          ; clear halt condition
+
+       #define zero i2
+       ; disable periphials (timer0), then set all pins as input+pullup to conserve battery.
+       LDI     x, 0x3 ; could use one-register to save on ROM (would keep adc enabled on attiny5/10)
+       OUT     PRR, x
+       OUT     DDRB, zero
+       LDI     x, 0x0f
+       OUT     PUEB, x
+
+       SBI     PCMSK, 2    ; listen for pin change on the audio out pin (i.e. wake up when a audio sink is connected)
+;TODO^: s/2/0/
+       SBI     PCICR, 0    ; enable PCINT0
+
+       ;enter power-down-mode
+       LDI     x, 0x05     ; sleep mode: power-down, enabled
+       OUT     SMCR, x
+       SLEEP
+       OUT     SMCR, one   ; sleep mode: idle, enabled
+
+       RJMP loop
+
+wakeup:
+       SBI     PCIFR, 0 ; clear interrupt
+       LDI     x, 0x05
+       OUT     DDRB, x
+       OUT     PUEB, zero
+       LDI     x, 0x02
+       OUT     PRR, x   ; not using zero, so devices with adc keep it disabled
+       RETI
+       #undef zero
+

 sample:
        OUT     OCR0AL, acc ; start by outputting a sample, because routine has variable runtime
 #ifdef DEBUG
 sample:
        OUT     OCR0AL, acc ; start by outputting a sample, because routine has variable runtime
 #ifdef DEBUG


@@ -354,60 +391,8 @@ sample:
        SBCI    i2, -1
        SBCI    i3, -1
 
        SBCI    i2, -1
        SBCI    i3, -1
 

-       CPI     i2, 0x78 ; 16m23 -- one loop
-       BREQ    halt
-continue:
-

 #ifdef DEBUG
        CBI     PORTB, 2   ; end runtime measurement
 #endif // DEBUG
        OUT     TIFR0, one ; clear pending interrupt (routine takes two intr.cycles)
        RETI ; reenables interrupts
 #ifdef DEBUG
        CBI     PORTB, 2   ; end runtime measurement
 #endif // DEBUG
        OUT     TIFR0, one ; clear pending interrupt (routine takes two intr.cycles)
        RETI ; reenables interrupts

-
-;      POWER SAVING MODE
-;
-;      To reduce physical size, we won't use a latching power switch. Instead,
-;      playback will stop after a full iteration (16m23s). Then, a momentary
-;      button will trigger a RESET, INT0 or PCINT0 interrupt to resume
-;      playback.  Meanwhile, all periphials will be shut down and the clock
-;      turned off. The watchdog is permanently off to reduce power consumption.
-;      Note: it is not necessary to switch the clock source from the 8MHz
-;      oscillator to the 128kHz one, since power-down mode disables the clock
-;      completely.
-
-; TODO: if we are using pcint on the audio-out pin, we could instruct the user to short the audio plug to ground to start playback (which should be triggered by a connected audio source). this would eliminate the button (and associated wiring) completely.
-
-halt:
-       ;set all pins as input & enable pullups and disable periphials to conserve energy
-       LDI     x, 0x00
-       OUT     DDRB, x
-       LDI     x, 0x0f
-       OUT     PUEB, x
-       LDI     x, 0x3 ; bit0: disable Timer0, bit1: disable attiny5/10's ADC
-       OUT     PRR, x
-
-       SBI     PCMSK, 0 ; enable PCINT0 on PB0 (pin1; also audio out)
-       SBI     PCICR, 0 ; enable PCINT0
-       
-       ;enter power-down-mode
-       LDI     x, 0x05 ; power-down mode:____010_ ; enable:_______1
-       OUT     SMCR, x
-       CLR     x
-       SLEEP
-       OUT     SMCR, x
-
-       RJMP continue
-
-
-pcint_handler:
-       SBI     PCIFR, 0 ; clear interrupt
-       LDI     x, 0x05
-       OUT     DDRB, x
-       LDI     x, 0x00
-       OUT     PUEB, x
-       LDI     x, 0x02
-       OUT     PRR, x   ; reset prr (not using zero, so devices with adc keep it disabled)
-       ; TODO: should probably reset i0/i1/i2
-       RETI
-
-; XXX: 14 byte too large; should probably purge i3, rerun fakeasm-tests with length reduced to 7864320. a dedicated five-register will save 2 instructions, too.