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authorLeonard Kugis <leonard@kug.is>2022-04-25 18:48:41 +0200
committerLeonard Kugis <leonard@kug.is>2022-04-25 18:48:41 +0200
commit0d6c506efe38ba9bf69355609a01e8a7634eff69 (patch)
treecdc5ab812202f5ea1997cb6371e88ab92521fd9e /templed.asm
Initial commit
Diffstat (limited to 'templed.asm')
-rw-r--r--templed.asm71
1 files changed, 71 insertions, 0 deletions
diff --git a/templed.asm b/templed.asm
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index 0000000..dfe4131
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+++ b/templed.asm
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+.include "tn85def.inc"
+.def tmp0 = r16
+.def tmp1 = r17
+.def tmp2 = r18
+.def tmp3 = r19
+
+; Interrupt vectors
+.org 0x0000
+interrupts:
+ rjmp init
+ .org ADCCaddr
+ rjmp adc_isr
+
+.org INT_VECTORS_SIZE
+init:
+ ; Initialize stack pointer
+ ldi tmp0, HIGH(RAMEND)
+ out SPH, tmp0
+ ldi tmp0, LOW(RAMEND)
+ out SPL, tmp0
+ ; Set pin directions
+ ldi tmp0, 0b00010010
+ out DDRB, tmp0
+ ; Set default outputs
+ ;ldi tmp0, 0b00000010
+ ;out PORTB, tmp0
+ ; Initialize timer 0B
+ ldi tmp0, 0b00100011
+ out TCCR0A, tmp0
+ ldi tmp0, 0b00000001
+ out TCCR0B, tmp0
+ ; Initialize timer 1B
+ ldi tmp0, 0b00000001
+ out TCCR1, tmp0
+ ldi tmp0, 0b01100000
+ out GTCCR, tmp0
+ ; Enable interrupts
+ ldi tmp0, 0b10000000
+ out SREG, tmp0
+ ; Initialize ADC
+ ldi tmp0, 0b01000001
+ out ADMUX, tmp0
+ ldi tmp0, 0b10101000
+ out ADCSRA, tmp0
+ ; Start ADC conversion
+ sbi ADCSRA, ADSC
+
+main:
+ rjmp main
+
+adc_isr:
+ push tmp0
+ push tmp1
+ ; Read out ADC
+ in tmp0, ADCL
+ in tmp1, ADCH
+ ; Substract offset
+ subi tmp0, LOW(638)
+ sbci tmp1, HIGH(638)
+ ; Normalize to 8 bit for timer
+ lsr tmp1
+ ror tmp0
+ lsr tmp1
+ ror tmp0
+ ; Set as timer compare
+ out OCR0B, tmp0
+ com tmp0
+ out OCR1B, tmp0
+ pop tmp1
+ pop tmp0
+ reti