// main function; program starts here
void main(void)
{
unsigned char data = 0;
unsigned int battery_voltage = 0; // ADC reading of battery voltage
ports_initialize(); // set up ports
ADC_initialize(); // configure ADC
SPI_initialize(); // set up SPI module
sleep_initialize(); // set up sleep mode
ISR_initialize(); // set up ISR
while(1)
{
SLEEP(); // sleep PIC until WDT expires
time++; // increment time (+16s)
battery_voltage = ADC_read(0x09); // read battery voltage
if ( time >= 1 ) // 1*16s=16s
{
time = 0; // reset time
if(battery_voltage >= 690) //690 = 11v
{
LATCbits.LATC4 = 1; // turn relay on
SPI_enable(); // turn on SPI module
while( data != 0xDA ) // wait for shutdown command to be received
{
while(!SSP1STATbits.BF) // wait till data is in the buffer
{
CLRWDT();
}
data = SSP1BUF; // read data outside
}
data = 0x00;
SPI_disable(); // turn off SPI module
__delay_ms(10000); // wait for R Pi to shutdown
LATCbits.LATC4 = 0; // turn relay off
}
}
}
}
int main(void) {
// int i, j;
int sine_table[NTABLE], cosine_table[NTABLE];
int mseq_table[CYCLES * NTABLE * MSEQ_LENGTH];
float size;
float s;
// float aI, aQ;
// float uI[M]; // Store last M samples of yI
// float uQ[M]; // Store last M samples of yQ
// float vI, vQ;
// float xI, xQ;
// float w = 0;
// float wq = 0;
int spb = MSEQ_LENGTH * CYCLES * NTABLE;
int last_samples[spb * MSG_LEN];
int i = 0;
USART_initialize(3000000, 1); // set baud rate to 3,000,000
DAC_initialize(FS); // set sample rate
DAC_ready_flag = 0; // clear the DAC ready flag
DAC_start(); // start the DAC running
ADC_initialize(FS);
ADC_start();
ADC_ready_flag = 0; // clear the ADC ready flag
int mseq[MSEQ_LENGTH] = { 1, 0, 1, 0, 1, 0, 1 };
int msg_table[MSG_LEN * CYCLES * NTABLE];
int recieved[MSG_LEN];
//char message[MSG_LEN] = "testing";
int msg[MSG_LEN] = { 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0 };
size = (float) (NTABLE / TABCYCLES);
for (i = 0; i < NTABLE; i++) {
sine_table[i] = (int) floor(32767 * sin(2.0 * PI * i / (float) size));
cosine_table[i] = (int) floor(32767 * cos(2.0 * PI * i / (float) size));
}
for (i = 0; i < spb; i++) {
mseq_table[i] =
(mseq[i / (NTABLE * CYCLES)]) ?
-sine_table[i % NTABLE] : cosine_table[i % NTABLE];
}
for (i = 0; i < CYCLES * NTABLE * MSG_LEN; i++) {
msg_table[i] =
(msg[i / (CYCLES * NTABLE)]) ?
-sine_table[i % NTABLE] : sine_table[i % NTABLE];
}
for (i = 0; i < MSG_LEN; i++) {
recieved[i] = 0;
}
i = 0;
int m = 0;
int strength = 0;
int maxstrength = 0;
for (i = 0; i < spb; i++) {
last_samples[i] = 0;
}
int cycles = 0;
int seconds = 0;
int state = 0; // 0: listening for mseq
// 4: initializing collection of packet data
// 5: collecting packet data
// 6: decoding & printing data
while (1) {
if (ADC_ready_flag != 0 && DAC_ready_flag != 0) {
ADC_ready_flag = 0;
DAC_ready_flag = 0;
if (state == 0) {
DAC1_value = mseq_table[m];
s = ADC1_value + 15000; // PIN 35A - Grab ADC value
last_samples[m] = s;
strength = 0;
for (i = 0; i < spb; i++) { // Slow?
strength +=
(last_samples[(m + 1 + i) % spb] * mseq_table[i])
/ 32767;
}
strength /= 100;
m++;
m = m % spb;
cycles++;
cycles = cycles % FS;
if (strength > 7500)
printf("Convolution: %i \n", strength);
if (strength > 7500) {
printf("CAUGHT MSEQ\n");
state = 4;
m = 0;
}
if (strength > maxstrength) {
maxstrength = strength;
printf("Max Strength: ");
printf("%i", maxstrength);
printf("\n");
}
if (cycles == 0) {
seconds++;
printf("[O3] Seconds elapsed: ");
printf("%i", seconds);
printf("\n");
}
} else if (state == 4) {
if (m == -1) {
m = 0;
state = 5;
last_samples[m] = ADC1_value + 15000;
m = 1;
DAC1_value = msg_table[m];
} else {
m = -1;
};
DAC1_value = msg_table[0];
} else if (state == 5) {
s = ADC1_value + 15000;
last_samples[m] = s;
int zero_s = 0;
int one_s = 0;
if (((m + 1) % (CYCLES * NTABLE)) == 0) {
zero_s = 0;
one_s = 0;
for (i = (((m + 1) - (CYCLES * NTABLE))); i <= m; i++) {
one_s += ((last_samples[i]) / 100)
* ((-sine_table[i % NTABLE]) / 100);
zero_s += ((last_samples[i]) / 100)
* ((sine_table[i % NTABLE]) / 100);
}
printf("zero strength: %i\n", zero_s);
printf("one strength: %i\n", one_s);
if (zero_s > one_s) {
printf("got 0\n");
recieved[((m + 1) / (CYCLES * NTABLE)) - 1] += 0;
} else {
printf("got 1\n");
recieved[((m + 1) / (CYCLES * NTABLE)) - 1] += 1;
}
}
if (m == CYCLES * NTABLE * MSG_LEN)
state = 6;
m++;
DAC1_value = msg_table[m];
} else if (state == 6) {
if (m < 20000)
m++;
else {
state = 4;
for (i = 0; i < MSG_LEN; i++) {
printf("%i ", recieved[i]);
}
printf("\n");
}
}
}
}
}
