I am frustrated!

main
Mike Lynch 2024-01-03 11:50:22 +11:00
parent cdeb974109
commit 5c8e20e17d
1 changed files with 38 additions and 18 deletions

View File

@ -10,21 +10,39 @@ Adafruit_MCP4728 mcp;
#define nsamp 256
#define dacmax 256
const byte nclk=42; //number of clock cycles of the loop
long int freq; //frequency in mHz
const byte nclk = 200; // a guess
long int freq; //frequency in Hz
long unsigned int phase;
long unsigned int phase_inc;
void setup() {
//TIMSK0 &= ~_BV(TOIE0); // disable timer0 overflow interrupt
//Wire.setClock(1400000L); // wooooo
// // Set a timer interrupt for the phase accumulation
cli();//stop interrupts
//set timer1 interrupt at 44Hz
TCCR1A = 0;// set entire TCCR1A register to 0
TCCR1B = 0;// same for TCCR1B
TCNT1 = 0;//initialize counter value to 0
// set compare match register for 1hz increments
OCR1A = 500; // = (16 * 10**6) / (44000) - 1
// turn on CTC mode
TCCR1B |= (1 << WGM12);
// Set CS10 and CS12 bits for 1024 prescaler
TCCR1B |= (1 << CS12) | (1 << CS10);
// enable timer compare interrupt
TIMSK1 |= (1 << OCIE1A);
sei();//allow interrupts
Serial.begin(115200);
while (!Serial)
delay(10); // will pause Zero, Leonardo, etc until serial console opens
// Try to initialize!
if (!mcp.begin(0x64)) {
Serial.println("Failed to find MCP4728 chip");
while (1) {
@ -34,11 +52,11 @@ void setup() {
Serial.println("Adafruit MCP4728 initialised");
}
Wire.setClock(3400000L);
freq=660;
freq=6600000;
phase=0;
calc_phase_inc();
//phase_inc = 1;
setwave();
}
@ -52,10 +70,10 @@ void setwave(){
int val=0;
//saw
val = dacmax * isamp / nsamp;
//val = dacmax * isamp / nsamp;
//val = ( isamp < nsamp / 2 ) ? 0 : dacmax - 1;
//sine
//val=(sin(phi)+1.0)*dacmax/2;
val=(sin(phi)+1.0)*dacmax/2;
//val=((sin(phi)+0.333*sin(3*phi))/0.943+1)*dacmax/2;
val=max(val,0);
@ -65,19 +83,21 @@ void setwave(){
}
//calculate the phase increment. 2^32/16E6=268.435456
//calculate the phase increment.
void calc_phase_inc(){
phase_inc=0.268435456*nclk*freq;
Serial.println("phase inc");
Serial.println(phase_inc);
}
//regular running: generate waves
ISR(TIMER1_COMPA_vect){// timer1 interrupt
phase += phase_inc;
}
//regular running:
void loop() {
//phase+=900;
//int redphase = phase >> 24;
phase += analogRead(A0);
int redphase = phase % nsamp;
int redphase = phase >> 24;
mcp.fastWrite(waveform[redphase] << 4, 0, 0, 0);
//Serial.println(redphase);
}