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Merge branch 'master' of github.com:c3d2/pentabug

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Conflicts:
	firmware/main.c
This commit is contained in:
john stone 2012-07-26 01:50:48 +02:00
commit 36cca6cfcf
2 changed files with 76 additions and 28 deletions
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2
firmware/Makefile
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@ -60,7 +60,7 @@ EXTRAINCDIRS =
# -Wall...: warning level # -Wall...: warning level
# -Wa,...: tell GCC to pass this to the assembler. # -Wa,...: tell GCC to pass this to the assembler.
# -ahlms: create assembler listing # -ahlms: create assembler listing
CFLAGS = -O$(OPT) CFLAGS = -O$(OPT) -g
CFLAGS += -funsigned-char CFLAGS += -funsigned-char
CFLAGS += -funsigned-bitfields CFLAGS += -funsigned-bitfields
CFLAGS += -fpack-struct CFLAGS += -fpack-struct

68
firmware/main.c
View File

@ -6,11 +6,54 @@
#include "main.h" #include "main.h"
volatile uint8_t sample_pending;
//25kHz //25kHz
ISR(TIMER0_OVF_vect) ISR(TIMER0_OVF_vect)
{ {
ICR1 = synth.output;
sample_pending = 1;
}
// sample rate is 8M / (5 * 64) = 25000
enum {
synth_channel_count = 2
};
typedef struct {
uint16_t phase;
uint16_t speed;
} synth_channel_t;
typedef struct {
synth_channel_t channels[synth_channel_count];
uint16_t output;
} synth_t;
static synth_t synth;
static void synth_init(void)
{
// some test values
synth.channels[0].phase = 0;
synth.channels[0].speed = 1153;
synth.channels[1].phase = 0;
synth.channels[1].speed = 23456;
}
static inline void synth_mix(void)
{
synth.output = 0;
for (int i = 0; i < synth_channel_count; i++) {
synth_channel_t *chan = &synth.channels[i];
chan->phase += chan->speed;
synth.output += (chan->phase >> 16) & 0xff;
}
} }
static void init_sampletimer(void) static void init_sampletimer(void)
@ -27,7 +70,6 @@ static void init_sampletimer(void)
TIMSK0 |= (1 << TOIE0); TIMSK0 |= (1 << TOIE0);
} }
static inline void init_pwm(void) static inline void init_pwm(void)
{ {
//PB1 set to output: //PB1 set to output:
@ -68,17 +110,16 @@ static void stupid_pwmtest(void)
{ {
uint8_t i, t, r; uint8_t i, t, r;
ICR1 = 0xAA00; ICR1 = 0xAA00;
r=1; t = r = 1;
for (;;) { for (;;) {
t = (r) ? (t + 1) : (t - 1); t = (r) ? (t + 1) : (t - 1);
ICR1 = (t << 7); ICR1 = (t << 7);
if(t=0) r ^= 1; if (t == 0)
for(i=1;i<100;i++) __asm("nop"); r ^= 1;
for (i = 1; i < 100; i++)
__asm("nop");
} }
return; //never return; //never
@ -91,10 +132,17 @@ int main(void)
init_leds(); init_leds();
init_motor(); init_motor();
init_pwm(); init_pwm();
sample_pending=0;
synth_init();
//just stupid test for now.... sei();
stupid_pwmtest();
while(1){
while (0 == sample_pending) ;
sample_pending = 0;
synth_mix();
}
//never get here //never get here
return; return 0;
} }