kopia lustrzana https://github.com/markqvist/LibAPRS
Working version
Mark Qvist
rodzic
bc77ed0b50
commit
8f8e124e38
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@ -0,0 +1,472 @@
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#include <string.h>
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#include "AFSK.h"
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extern unsigned long custom_preamble;
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extern unsigned long custom_tail;
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bool hw_afsk_dac_isr = false;
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bool hw_5v_ref = false;
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Afsk *AFSK_modem;
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// Forward declerations
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int afsk_getchar(void);
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void afsk_putchar(char c);
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void AFSK_hw_refDetect(void) {
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// This is manual for now
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#if ADC_REFERENCE == REF_5V
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hw_5v_ref = true;
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#else
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hw_5v_ref = false;
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#endif
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}
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void AFSK_hw_init(void) {
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// Set up ADC
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AFSK_hw_refDetect();
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TCCR1A = 0;
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TCCR1B = _BV(CS10) | _BV(WGM13) | _BV(WGM12);
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ICR1 = (((CPU_FREQ+FREQUENCY_CORRECTION)) / 9600) - 1;
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if (hw_5v_ref) {
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ADMUX = _BV(REFS0) | 0;
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} else {
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ADMUX = 0;
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}
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ADC_DDR &= ~_BV(0);
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ADC_PORT &= ~_BV(0);
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DIDR0 |= _BV(0);
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ADCSRB = _BV(ADTS2) |
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_BV(ADTS1) |
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_BV(ADTS0);
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ADCSRA = _BV(ADEN) |
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_BV(ADSC) |
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_BV(ADATE)|
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_BV(ADIE) |
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_BV(ADPS2);
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AFSK_DAC_INIT();
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LED_TX_INIT();
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LED_RX_INIT();
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}
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void AFSK_init(Afsk *afsk) {
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// Allocate modem struct memory
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memset(afsk, 0, sizeof(*afsk));
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AFSK_modem = afsk;
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// Set phase increment
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afsk->phaseInc = MARK_INC;
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// Initialise FIFO buffers
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fifo_init(&afsk->delayFifo, (uint8_t *)afsk->delayBuf, sizeof(afsk->delayBuf));
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fifo_init(&afsk->rxFifo, afsk->rxBuf, sizeof(afsk->rxBuf));
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fifo_init(&afsk->txFifo, afsk->txBuf, sizeof(afsk->txBuf));
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// Fill delay FIFO with zeroes
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for (int i = 0; i<SAMPLESPERBIT / 2; i++) {
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fifo_push(&afsk->delayFifo, 0);
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}
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AFSK_hw_init();
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}
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static void AFSK_txStart(Afsk *afsk) {
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if (!afsk->sending) {
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afsk->phaseInc = MARK_INC;
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afsk->phaseAcc = 0;
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afsk->bitstuffCount = 0;
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afsk->sending = true;
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LED_TX_ON();
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afsk->preambleLength = DIV_ROUND(custom_preamble * BITRATE, 8000);
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AFSK_DAC_IRQ_START();
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}
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ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
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afsk->tailLength = DIV_ROUND(custom_tail * BITRATE, 8000);
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}
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}
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void afsk_putchar(char c) {
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AFSK_txStart(AFSK_modem);
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while(fifo_isfull_locked(&AFSK_modem->txFifo)) { /* Wait */ }
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fifo_push_locked(&AFSK_modem->txFifo, c);
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}
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int afsk_getchar(void) {
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if (fifo_isempty_locked(&AFSK_modem->rxFifo)) {
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return EOF;
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} else {
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return fifo_pop_locked(&AFSK_modem->rxFifo);
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}
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}
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void AFSK_transmit(char *buffer, size_t size) {
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fifo_flush(&AFSK_modem->txFifo);
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int i = 0;
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while (size--) {
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afsk_putchar(buffer[i++]);
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}
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}
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uint8_t AFSK_dac_isr(Afsk *afsk) {
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if (afsk->sampleIndex == 0) {
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if (afsk->txBit == 0) {
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if (fifo_isempty(&afsk->txFifo) && afsk->tailLength == 0) {
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AFSK_DAC_IRQ_STOP();
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afsk->sending = false;
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LED_TX_OFF();
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return 0;
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} else {
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if (!afsk->bitStuff) afsk->bitstuffCount = 0;
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afsk->bitStuff = true;
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if (afsk->preambleLength == 0) {
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if (fifo_isempty(&afsk->txFifo)) {
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afsk->tailLength--;
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afsk->currentOutputByte = HDLC_FLAG;
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} else {
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afsk->currentOutputByte = fifo_pop(&afsk->txFifo);
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}
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} else {
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afsk->preambleLength--;
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afsk->currentOutputByte = HDLC_FLAG;
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}
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if (afsk->currentOutputByte == AX25_ESC) {
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if (fifo_isempty(&afsk->txFifo)) {
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AFSK_DAC_IRQ_STOP();
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afsk->sending = false;
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LED_TX_OFF();
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return 0;
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} else {
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afsk->currentOutputByte = fifo_pop(&afsk->txFifo);
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}
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} else if (afsk->currentOutputByte == HDLC_FLAG || afsk->currentOutputByte == HDLC_RESET) {
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afsk->bitStuff = false;
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}
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}
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afsk->txBit = 0x01;
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}
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if (afsk->bitStuff && afsk->bitstuffCount >= BIT_STUFF_LEN) {
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afsk->bitstuffCount = 0;
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afsk->phaseInc = SWITCH_TONE(afsk->phaseInc);
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} else {
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if (afsk->currentOutputByte & afsk->txBit) {
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afsk->bitstuffCount++;
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} else {
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afsk->bitstuffCount = 0;
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afsk->phaseInc = SWITCH_TONE(afsk->phaseInc);
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}
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afsk->txBit <<= 1;
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}
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afsk->sampleIndex = SAMPLESPERBIT;
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}
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afsk->phaseAcc += afsk->phaseInc;
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afsk->phaseAcc %= SIN_LEN;
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afsk->sampleIndex--;
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return sinSample(afsk->phaseAcc);
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}
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static bool hdlcParse(Hdlc *hdlc, bool bit, FIFOBuffer *fifo) {
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// Initialise a return value. We start with the
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// assumption that all is going to end well :)
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bool ret = true;
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// Bitshift our byte of demodulated bits to
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// the left by one bit, to make room for the
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// next incoming bit
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hdlc->demodulatedBits <<= 1;
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// And then put the newest bit from the
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// demodulator into the byte.
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hdlc->demodulatedBits |= bit ? 1 : 0;
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// Now we'll look at the last 8 received bits, and
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// check if we have received a HDLC flag (01111110)
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if (hdlc->demodulatedBits == HDLC_FLAG) {
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// If we have, check that our output buffer is
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// not full.
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if (!fifo_isfull(fifo)) {
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// If it isn't, we'll push the HDLC_FLAG into
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// the buffer and indicate that we are now
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// receiving data. For bling we also turn
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// on the RX LED.
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fifo_push(fifo, HDLC_FLAG);
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hdlc->receiving = true;
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#if OPEN_SQUELCH == false
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LED_RX_ON();
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#endif
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} else {
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// If the buffer is full, we have a problem
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// and abort by setting the return value to
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// false and stopping the here.
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ret = false;
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hdlc->receiving = false;
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LED_RX_OFF();
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}
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// Everytime we receive a HDLC_FLAG, we reset the
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// storage for our current incoming byte and bit
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// position in that byte. This effectively
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// synchronises our parsing to the start and end
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// of the received bytes.
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hdlc->currentByte = 0;
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hdlc->bitIndex = 0;
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return ret;
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}
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// Check if we have received a RESET flag (01111111)
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// In this comparison we also detect when no transmission
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// (or silence) is taking place, and the demodulator
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// returns an endless stream of zeroes. Due to the NRZ
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// coding, the actual bits send to this function will
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// be an endless stream of ones, which this AND operation
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// will also detect.
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if ((hdlc->demodulatedBits & HDLC_RESET) == HDLC_RESET) {
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// If we have, something probably went wrong at the
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// transmitting end, and we abort the reception.
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hdlc->receiving = false;
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LED_RX_OFF();
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return ret;
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}
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// If we have not yet seen a HDLC_FLAG indicating that
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// a transmission is actually taking place, don't bother
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// with anything.
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if (!hdlc->receiving)
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return ret;
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// First check if what we are seeing is a stuffed bit.
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// Since the different HDLC control characters like
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// HDLC_FLAG, HDLC_RESET and such could also occur in
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// a normal data stream, we employ a method known as
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// "bit stuffing". All control characters have more than
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// 5 ones in a row, so if the transmitting party detects
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// this sequence in the _data_ to be transmitted, it inserts
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// a zero to avoid the receiving party interpreting it as
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// a control character. Therefore, if we detect such a
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// "stuffed bit", we simply ignore it and wait for the
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// next bit to come in.
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//
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// We do the detection by applying an AND bit-mask to the
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// stream of demodulated bits. This mask is 00111111 (0x3f)
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// if the result of the operation is 00111110 (0x3e), we
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// have detected a stuffed bit.
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if ((hdlc->demodulatedBits & 0x3f) == 0x3e)
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return ret;
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// If we have an actual 1 bit, push this to the current byte
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// If it's a zero, we don't need to do anything, since the
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// bit is initialized to zero when we bitshifted earlier.
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if (hdlc->demodulatedBits & 0x01)
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hdlc->currentByte |= 0x80;
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// Increment the bitIndex and check if we have a complete byte
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if (++hdlc->bitIndex >= 8) {
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// If we have a HDLC control character, put a AX.25 escape
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// in the received data. We know we need to do this,
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// because at this point we must have already seen a HDLC
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// flag, meaning that this control character is the result
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// of a bitstuffed byte that is equal to said control
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// character, but is actually part of the data stream.
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// By inserting the escape character, we tell the protocol
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// layer that this is not an actual control character, but
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// data.
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if ((hdlc->currentByte == HDLC_FLAG ||
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hdlc->currentByte == HDLC_RESET ||
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hdlc->currentByte == AX25_ESC)) {
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// We also need to check that our received data buffer
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// is not full before putting more data in
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if (!fifo_isfull(fifo)) {
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fifo_push(fifo, AX25_ESC);
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} else {
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// If it is, abort and return false
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hdlc->receiving = false;
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LED_RX_OFF();
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ret = false;
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}
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}
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// Push the actual byte to the received data FIFO,
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// if it isn't full.
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if (!fifo_isfull(fifo)) {
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fifo_push(fifo, hdlc->currentByte);
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} else {
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// If it is, well, you know by now!
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hdlc->receiving = false;
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LED_RX_OFF();
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ret = false;
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}
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// Wipe received byte and reset bit index to 0
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hdlc->currentByte = 0;
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hdlc->bitIndex = 0;
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} else {
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// We don't have a full byte yet, bitshift the byte
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// to make room for the next bit
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hdlc->currentByte >>= 1;
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}
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//digitalWrite(13, LOW);
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return ret;
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}
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void AFSK_adc_isr(Afsk *afsk, int8_t currentSample) {
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// To determine the received frequency, and thereby
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// the bit of the sample, we multiply the sample by
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// a sample delayed by (samples per bit / 2).
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// We then lowpass-filter the samples with a
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// Chebyshev filter. The lowpass filtering serves
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// to "smooth out" the variations in the samples.
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afsk->iirX[0] = afsk->iirX[1];
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afsk->iirX[1] = ((int8_t)fifo_pop(&afsk->delayFifo) * currentSample) >> 2;
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afsk->iirY[0] = afsk->iirY[1];
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afsk->iirY[1] = afsk->iirX[0] + afsk->iirX[1] + (afsk->iirY[0] >> 1); // Chebyshev filter
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// We put the sampled bit in a delay-line:
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// First we bitshift everything 1 left
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afsk->sampledBits <<= 1;
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// And then add the sampled bit to our delay line
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afsk->sampledBits |= (afsk->iirY[1] > 0) ? 1 : 0;
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// Put the current raw sample in the delay FIFO
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fifo_push(&afsk->delayFifo, currentSample);
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// We need to check whether there is a signal transition.
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// If there is, we can recalibrate the phase of our
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// sampler to stay in sync with the transmitter. A bit of
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// explanation is required to understand how this works.
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// Since we have PHASE_MAX/PHASE_BITS = 8 samples per bit,
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// we employ a phase counter (currentPhase), that increments
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// by PHASE_BITS everytime a sample is captured. When this
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// counter reaches PHASE_MAX, it wraps around by modulus
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// PHASE_MAX. We then look at the last three samples we
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// captured and determine if the bit was a one or a zero.
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//
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// This gives us a "window" looking into the stream of
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// samples coming from the ADC. Sort of like this:
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//
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// Past Future
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// 0000000011111111000000001111111100000000
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// |________|
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// ||
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// Window
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//
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// Every time we detect a signal transition, we adjust
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// where this window is positioned little. How much we
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// adjust it is defined by PHASE_INC. If our current phase
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// phase counter value is less than half of PHASE_MAX (ie,
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// the window size) when a signal transition is detected,
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// add PHASE_INC to our phase counter, effectively moving
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// the window a little bit backward (to the left in the
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// illustration), inversely, if the phase counter is greater
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// than half of PHASE_MAX, we move it forward a little.
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// This way, our "window" is constantly seeking to position
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// it's center at the bit transitions. Thus, we synchronise
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// our timing to the transmitter, even if it's timing is
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// a little off compared to our own.
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if (SIGNAL_TRANSITIONED(afsk->sampledBits)) {
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if (afsk->currentPhase < PHASE_THRESHOLD) {
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afsk->currentPhase += PHASE_INC;
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} else {
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afsk->currentPhase -= PHASE_INC;
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}
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}
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// We increment our phase counter
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afsk->currentPhase += PHASE_BITS;
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// Check if we have reached the end of
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// our sampling window.
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if (afsk->currentPhase >= PHASE_MAX) {
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// If we have, wrap around our phase
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// counter by modulus
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afsk->currentPhase %= PHASE_MAX;
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// Bitshift to make room for the next
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// bit in our stream of demodulated bits
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afsk->actualBits <<= 1;
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// We determine the actual bit value by reading
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// the last 3 sampled bits. If there is three or
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// more 1's, we will assume that the transmitter
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// sent us a one, otherwise we assume a zero
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uint8_t bits = afsk->sampledBits & 0x07;
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if (bits == 0x07 || // 111
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bits == 0x06 || // 110
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bits == 0x05 || // 101
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bits == 0x03 // 011
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) {
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afsk->actualBits |= 1;
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}
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//// Alternative using five bits ////////////////
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// uint8_t bits = afsk->sampledBits & 0x0f;
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// uint8_t c = 0;
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// c += bits & BV(1);
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// c += bits & BV(2);
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// c += bits & BV(3);
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// c += bits & BV(4);
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// c += bits & BV(5);
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// if (c >= 3) afsk->actualBits |= 1;
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/////////////////////////////////////////////////
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// Now we can pass the actual bit to the HDLC parser.
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// We are using NRZ coding, so if 2 consecutive bits
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// have the same value, we have a 1, otherwise a 0.
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// We use the TRANSITION_FOUND function to determine this.
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//
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// This is smart in combination with bit stuffing,
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// since it ensures a transmitter will never send more
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// than five consecutive 1's. When sending consecutive
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// ones, the signal stays at the same level, and if
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// this happens for longer periods of time, we would
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// not be able to synchronize our phase to the transmitter
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// and would start experiencing "bit slip".
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//
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// By combining bit-stuffing with NRZ coding, we ensure
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// that the signal will regularly make transitions
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// that we can use to synchronize our phase.
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//
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// We also check the return of the Link Control parser
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// to check if an error occured.
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if (!hdlcParse(&afsk->hdlc, !TRANSITION_FOUND(afsk->actualBits), &afsk->rxFifo)) {
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afsk->status |= 1;
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if (fifo_isfull(&afsk->rxFifo)) {
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fifo_flush(&afsk->rxFifo);
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afsk->status = 0;
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}
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}
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}
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}
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extern void APRS_poll();
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uint8_t poll_timer = 0;
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ISR(ADC_vect) {
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TIFR1 = _BV(ICF1);
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AFSK_adc_isr(AFSK_modem, ((int16_t)((ADC) >> 2) - 128));
|
||||
if (hw_afsk_dac_isr) {
|
||||
DAC_PORT = (AFSK_dac_isr(AFSK_modem) & 0xF0) | _BV(3);
|
||||
} else {
|
||||
DAC_PORT = 128;
|
||||
}
|
||||
|
||||
poll_timer++;
|
||||
if (poll_timer > 4) {
|
||||
poll_timer = 0;
|
||||
APRS_poll();
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,138 @@
|
|||
#ifndef AFSK_H
|
||||
#define AFSK_H
|
||||
|
||||
#include "device.h"
|
||||
#include <stdint.h>
|
||||
#include <stdbool.h>
|
||||
#include <stdio.h>
|
||||
#include <avr/pgmspace.h>
|
||||
#include "FIFO.h"
|
||||
#include "HDLC.h"
|
||||
|
||||
#define SIN_LEN 512
|
||||
static const uint8_t sin_table[] PROGMEM =
|
||||
{
|
||||
128, 129, 131, 132, 134, 135, 137, 138, 140, 142, 143, 145, 146, 148, 149, 151,
|
||||
152, 154, 155, 157, 158, 160, 162, 163, 165, 166, 167, 169, 170, 172, 173, 175,
|
||||
176, 178, 179, 181, 182, 183, 185, 186, 188, 189, 190, 192, 193, 194, 196, 197,
|
||||
198, 200, 201, 202, 203, 205, 206, 207, 208, 210, 211, 212, 213, 214, 215, 217,
|
||||
218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233,
|
||||
234, 234, 235, 236, 237, 238, 238, 239, 240, 241, 241, 242, 243, 243, 244, 245,
|
||||
245, 246, 246, 247, 248, 248, 249, 249, 250, 250, 250, 251, 251, 252, 252, 252,
|
||||
253, 253, 253, 253, 254, 254, 254, 254, 254, 255, 255, 255, 255, 255, 255, 255,
|
||||
};
|
||||
|
||||
inline static uint8_t sinSample(uint16_t i) {
|
||||
uint16_t newI = i % (SIN_LEN/2);
|
||||
newI = (newI >= (SIN_LEN/4)) ? (SIN_LEN/2 - newI -1) : newI;
|
||||
uint8_t sine = pgm_read_byte(&sin_table[newI]);
|
||||
return (i >= (SIN_LEN/2)) ? (255 - sine) : sine;
|
||||
}
|
||||
|
||||
|
||||
#define SWITCH_TONE(inc) (((inc) == MARK_INC) ? SPACE_INC : MARK_INC)
|
||||
#define BITS_DIFFER(bits1, bits2) (((bits1)^(bits2)) & 0x01)
|
||||
#define DUAL_XOR(bits1, bits2) ((((bits1)^(bits2)) & 0x03) == 0x03)
|
||||
#define SIGNAL_TRANSITIONED(bits) DUAL_XOR((bits), (bits) >> 2)
|
||||
#define TRANSITION_FOUND(bits) BITS_DIFFER((bits), (bits) >> 1)
|
||||
|
||||
#define CPU_FREQ F_CPU
|
||||
|
||||
#define CONFIG_AFSK_RX_BUFLEN 64
|
||||
#define CONFIG_AFSK_TX_BUFLEN 64
|
||||
#define CONFIG_AFSK_RXTIMEOUT 0
|
||||
#define CONFIG_AFSK_PREAMBLE_LEN 150UL
|
||||
#define CONFIG_AFSK_TRAILER_LEN 50UL
|
||||
#define SAMPLERATE 9600
|
||||
#define BITRATE 1200
|
||||
#define SAMPLESPERBIT (SAMPLERATE / BITRATE)
|
||||
#define BIT_STUFF_LEN 5
|
||||
#define MARK_FREQ 1200
|
||||
#define SPACE_FREQ 2200
|
||||
#define PHASE_BITS 8 // How much to increment phase counter each sample
|
||||
#define PHASE_INC 1 // Nudge by an eigth of a sample each adjustment
|
||||
#define PHASE_MAX (SAMPLESPERBIT * PHASE_BITS) // Resolution of our phase counter = 64
|
||||
#define PHASE_THRESHOLD (PHASE_MAX / 2) // Target transition point of our phase window
|
||||
|
||||
|
||||
typedef struct Hdlc
|
||||
{
|
||||
uint8_t demodulatedBits;
|
||||
uint8_t bitIndex;
|
||||
uint8_t currentByte;
|
||||
bool receiving;
|
||||
} Hdlc;
|
||||
|
||||
typedef struct Afsk
|
||||
{
|
||||
// Stream access to modem
|
||||
FILE fd;
|
||||
|
||||
// General values
|
||||
Hdlc hdlc; // We need a link control structure
|
||||
uint16_t preambleLength; // Length of sync preamble
|
||||
uint16_t tailLength; // Length of transmission tail
|
||||
|
||||
// Modulation values
|
||||
uint8_t sampleIndex; // Current sample index for outgoing bit
|
||||
uint8_t currentOutputByte; // Current byte to be modulated
|
||||
uint8_t txBit; // Mask of current modulated bit
|
||||
bool bitStuff; // Whether bitstuffing is allowed
|
||||
|
||||
uint8_t bitstuffCount; // Counter for bit-stuffing
|
||||
|
||||
uint16_t phaseAcc; // Phase accumulator
|
||||
uint16_t phaseInc; // Phase increment per sample
|
||||
|
||||
FIFOBuffer txFifo; // FIFO for transmit data
|
||||
uint8_t txBuf[CONFIG_AFSK_TX_BUFLEN]; // Actial data storage for said FIFO
|
||||
|
||||
volatile bool sending; // Set when modem is sending
|
||||
|
||||
// Demodulation values
|
||||
FIFOBuffer delayFifo; // Delayed FIFO for frequency discrimination
|
||||
int8_t delayBuf[SAMPLESPERBIT / 2 + 1]; // Actual data storage for said FIFO
|
||||
|
||||
FIFOBuffer rxFifo; // FIFO for received data
|
||||
uint8_t rxBuf[CONFIG_AFSK_RX_BUFLEN]; // Actual data storage for said FIFO
|
||||
|
||||
int16_t iirX[2]; // IIR Filter X cells
|
||||
int16_t iirY[2]; // IIR Filter Y cells
|
||||
|
||||
uint8_t sampledBits; // Bits sampled by the demodulator (at ADC speed)
|
||||
int8_t currentPhase; // Current phase of the demodulator
|
||||
uint8_t actualBits; // Actual found bits at correct bitrate
|
||||
|
||||
volatile int status; // Status of the modem, 0 means OK
|
||||
|
||||
} Afsk;
|
||||
|
||||
#define DIV_ROUND(dividend, divisor) (((dividend) + (divisor) / 2) / (divisor))
|
||||
#define MARK_INC (uint16_t)(DIV_ROUND(SIN_LEN * (uint32_t)MARK_FREQ, CONFIG_AFSK_DAC_SAMPLERATE))
|
||||
#define SPACE_INC (uint16_t)(DIV_ROUND(SIN_LEN * (uint32_t)SPACE_FREQ, CONFIG_AFSK_DAC_SAMPLERATE))
|
||||
|
||||
#define AFSK_DAC_IRQ_START() do { extern bool hw_afsk_dac_isr; hw_afsk_dac_isr = true; } while (0)
|
||||
#define AFSK_DAC_IRQ_STOP() do { extern bool hw_afsk_dac_isr; hw_afsk_dac_isr = false; } while (0)
|
||||
#define AFSK_DAC_INIT() do { DAC_DDR |= 0xF8; } while (0)
|
||||
|
||||
// Here's some macros for controlling the RX/TX LEDs
|
||||
// THE _INIT() functions writes to the DDRB register
|
||||
// to configure the pins as output pins, and the _ON()
|
||||
// and _OFF() functions writes to the PORT registers
|
||||
// to turn the pins on or off.
|
||||
#define LED_TX_INIT() do { LED_DDR |= _BV(1); } while (0)
|
||||
#define LED_TX_ON() do { LED_PORT |= _BV(1); } while (0)
|
||||
#define LED_TX_OFF() do { LED_PORT &= ~_BV(1); } while (0)
|
||||
|
||||
#define LED_RX_INIT() do { LED_DDR |= _BV(2); } while (0)
|
||||
#define LED_RX_ON() do { LED_PORT |= _BV(2); } while (0)
|
||||
#define LED_RX_OFF() do { LED_PORT &= ~_BV(2); } while (0)
|
||||
|
||||
void AFSK_init(Afsk *afsk);
|
||||
void AFSK_transmit(char *buffer, size_t size);
|
||||
void AFSK_poll(Afsk *afsk);
|
||||
|
||||
void afsk_putchar(char c);
|
||||
int afsk_getchar(void);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,155 @@
|
|||
// Based on work by Francesco Sacchi
|
||||
|
||||
#include "Arduino.h"
|
||||
#include <string.h>
|
||||
#include <ctype.h>
|
||||
#include "AX25.h"
|
||||
#include "HDLC.h"
|
||||
#include "CRC-CCIT.h"
|
||||
#include "AFSK.h"
|
||||
|
||||
#define countof(a) sizeof(a)/sizeof(a[0])
|
||||
#define MIN(a,b) ({ typeof(a) _a = (a); typeof(b) _b = (b); ((typeof(_a))((_a < _b) ? _a : _b)); })
|
||||
#define DECODE_CALL(buf, addr) for (unsigned i = 0; i < sizeof((addr)); i++) { char c = (*(buf)++ >> 1); (addr)[i] = (c == ' ') ? '\x0' : c; }
|
||||
#define AX25_SET_REPEATED(msg, idx, val) do { if (val) { (msg)->rpt_flags |= _BV(idx); } else { (msg)->rpt_flags &= ~_BV(idx) ; } } while(0)
|
||||
|
||||
void ax25_init(AX25Ctx *ctx, ax25_callback_t hook) {
|
||||
memset(ctx, 0, sizeof(*ctx));
|
||||
ctx->hook = hook;
|
||||
ctx->crc_in = ctx->crc_out = CRC_CCIT_INIT_VAL;
|
||||
}
|
||||
|
||||
static void ax25_decode(AX25Ctx *ctx) {
|
||||
AX25Msg msg;
|
||||
uint8_t *buf = ctx->buf;
|
||||
|
||||
DECODE_CALL(buf, msg.dst.call);
|
||||
msg.dst.ssid = (*buf++ >> 1) & 0x0F;
|
||||
|
||||
DECODE_CALL(buf, msg.src.call);
|
||||
msg.src.ssid = (*buf >> 1) & 0x0F;
|
||||
|
||||
for (msg.rpt_count = 0; !(*buf++ & 0x01) && (msg.rpt_count < countof(msg.rpt_list)); msg.rpt_count++) {
|
||||
DECODE_CALL(buf, msg.rpt_list[msg.rpt_count].call);
|
||||
msg.rpt_list[msg.rpt_count].ssid = (*buf >> 1) & 0x0F;
|
||||
AX25_SET_REPEATED(&msg, msg.rpt_count, (*buf & 0x80));
|
||||
}
|
||||
|
||||
msg.ctrl = *buf++;
|
||||
if (msg.ctrl != AX25_CTRL_UI) { return; }
|
||||
|
||||
msg.pid = *buf++;
|
||||
if (msg.pid != AX25_PID_NOLAYER3) { return; }
|
||||
|
||||
msg.len = ctx->frame_len - 2 - (buf - ctx->buf);
|
||||
msg.info = buf;
|
||||
|
||||
if (ctx->hook) ctx->hook(&msg);
|
||||
|
||||
}
|
||||
|
||||
void ax25_poll(AX25Ctx *ctx) {
|
||||
int c;
|
||||
|
||||
while ((c = afsk_getchar()) != EOF) {
|
||||
if (!ctx->escape && c == HDLC_FLAG) {
|
||||
if (ctx->frame_len >= AX25_MIN_FRAME_LEN) {
|
||||
if (ctx->crc_in == AX25_CRC_CORRECT) {
|
||||
#if OPEN_SQUELCH == true
|
||||
LED_RX_ON();
|
||||
#endif
|
||||
ax25_decode(ctx);
|
||||
}
|
||||
}
|
||||
ctx->sync = true;
|
||||
ctx->crc_in = CRC_CCIT_INIT_VAL;
|
||||
ctx->frame_len = 0;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (!ctx->escape && c == HDLC_RESET) {
|
||||
ctx->sync = false;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (!ctx->escape && c == AX25_ESC) {
|
||||
ctx->escape = true;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (ctx->sync) {
|
||||
if (ctx->frame_len < AX25_MAX_FRAME_LEN) {
|
||||
ctx->buf[ctx->frame_len++] = c;
|
||||
ctx->crc_in = update_crc_ccit(c, ctx->crc_in);
|
||||
} else {
|
||||
ctx->sync = false;
|
||||
}
|
||||
}
|
||||
ctx->escape = false;
|
||||
}
|
||||
}
|
||||
|
||||
static void ax25_putchar(AX25Ctx *ctx, uint8_t c)
|
||||
{
|
||||
if (c == HDLC_FLAG || c == HDLC_RESET || c == AX25_ESC) afsk_putchar(AX25_ESC);
|
||||
ctx->crc_out = update_crc_ccit(c, ctx->crc_out);
|
||||
afsk_putchar(c);
|
||||
}
|
||||
|
||||
void ax25_sendRaw(AX25Ctx *ctx, void *_buf, size_t len) {
|
||||
ctx->crc_out = CRC_CCIT_INIT_VAL;
|
||||
afsk_putchar(HDLC_FLAG);
|
||||
const uint8_t *buf = (const uint8_t *)_buf;
|
||||
while (len--) ax25_putchar(ctx, *buf++);
|
||||
|
||||
uint8_t crcl = (ctx->crc_out & 0xff) ^ 0xff;
|
||||
uint8_t crch = (ctx->crc_out >> 8) ^ 0xff;
|
||||
ax25_putchar(ctx, crcl);
|
||||
ax25_putchar(ctx, crch);
|
||||
|
||||
afsk_putchar(HDLC_FLAG);
|
||||
}
|
||||
|
||||
static void ax25_sendCall(AX25Ctx *ctx, const AX25Call *addr, bool last){
|
||||
unsigned len = MIN(sizeof(addr->call), strlen(addr->call));
|
||||
|
||||
for (unsigned i = 0; i < len; i++) {
|
||||
uint8_t c = addr->call[i];
|
||||
c = toupper(c);
|
||||
ax25_putchar(ctx, c << 1);
|
||||
}
|
||||
|
||||
if (len < sizeof(addr->call)) {
|
||||
for (unsigned i = 0; i < sizeof(addr->call) - len; i++) {
|
||||
ax25_putchar(ctx, ' ' << 1);
|
||||
}
|
||||
}
|
||||
|
||||
uint8_t ssid = 0x60 | (addr->ssid << 1) | (last ? 0x01 : 0);
|
||||
ax25_putchar(ctx, ssid);
|
||||
}
|
||||
|
||||
void ax25_sendVia(AX25Ctx *ctx, const AX25Call *path, size_t path_len, const void *_buf, size_t len) {
|
||||
const uint8_t *buf = (const uint8_t *)_buf;
|
||||
|
||||
ctx->crc_out = CRC_CCIT_INIT_VAL;
|
||||
afsk_putchar(HDLC_FLAG);
|
||||
|
||||
for (size_t i = 0; i < path_len; i++) {
|
||||
ax25_sendCall(ctx, &path[i], (i == path_len - 1));
|
||||
}
|
||||
|
||||
ax25_putchar(ctx, AX25_CTRL_UI);
|
||||
ax25_putchar(ctx, AX25_PID_NOLAYER3);
|
||||
|
||||
while (len--) {
|
||||
ax25_putchar(ctx, *buf++);
|
||||
}
|
||||
|
||||
uint8_t crcl = (ctx->crc_out & 0xff) ^ 0xff;
|
||||
uint8_t crch = (ctx->crc_out >> 8) ^ 0xff;
|
||||
ax25_putchar(ctx, crcl);
|
||||
ax25_putchar(ctx, crch);
|
||||
|
||||
afsk_putchar(HDLC_FLAG);
|
||||
}
|
||||
|
|
@ -0,0 +1,67 @@
|
|||
#ifndef PROTOCOL_AX25_H
|
||||
#define PROTOCOL_AX25_H
|
||||
|
||||
#include <stdio.h>
|
||||
#include <stdbool.h>
|
||||
#include "device.h"
|
||||
|
||||
#define AX25_MIN_FRAME_LEN 18
|
||||
#ifndef CUSTOM_FRAME_SIZE
|
||||
#define AX25_MAX_FRAME_LEN 620
|
||||
#else
|
||||
#define AX25_MAX_FRAME_LEN CUSTOM_FRAME_SIZE
|
||||
#endif
|
||||
|
||||
#define AX25_CRC_CORRECT 0xF0B8
|
||||
|
||||
#define AX25_CTRL_UI 0x03
|
||||
#define AX25_PID_NOLAYER3 0xF0
|
||||
|
||||
struct AX25Ctx; // Forward declarations
|
||||
struct AX25Msg;
|
||||
|
||||
typedef void (*ax25_callback_t)(struct AX25Msg *msg);
|
||||
|
||||
typedef struct AX25Ctx {
|
||||
uint8_t buf[AX25_MAX_FRAME_LEN];
|
||||
FILE *ch;
|
||||
size_t frame_len;
|
||||
uint16_t crc_in;
|
||||
uint16_t crc_out;
|
||||
ax25_callback_t hook;
|
||||
bool sync;
|
||||
bool escape;
|
||||
} AX25Ctx;
|
||||
|
||||
|
||||
#define AX25_CALL(str, id) {.call = (str), .ssid = (id) }
|
||||
#define AX25_MAX_RPT 8
|
||||
#define AX25_REPEATED(msg, n) ((msg)->rpt_flags & BV(n))
|
||||
|
||||
typedef struct AX25Call {
|
||||
char call[6];
|
||||
uint8_t ssid;
|
||||
} AX25Call;
|
||||
|
||||
typedef struct AX25Msg {
|
||||
AX25Call src;
|
||||
AX25Call dst;
|
||||
AX25Call rpt_list[AX25_MAX_RPT];
|
||||
uint8_t rpt_count;
|
||||
uint8_t rpt_flags;
|
||||
uint16_t ctrl;
|
||||
uint8_t pid;
|
||||
const uint8_t *info;
|
||||
size_t len;
|
||||
} AX25Msg;
|
||||
|
||||
void ax25_sendVia(AX25Ctx *ctx, const AX25Call *path, size_t path_len, const void *_buf, size_t len);
|
||||
#define ax25_send(ctx, dst, src, buf, len) ax25_sendVia(ctx, ({static AX25Call __path[]={dst, src}; __path;}), 2, buf, len)
|
||||
|
||||
|
||||
|
||||
void ax25_poll(AX25Ctx *ctx);
|
||||
void ax25_sendRaw(AX25Ctx *ctx, void *_buf, size_t len);
|
||||
void ax25_init(AX25Ctx *ctx, ax25_callback_t hook);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,36 @@
|
|||
#include "CRC-CCIT.h"
|
||||
|
||||
const uint16_t crc_ccit_table[256] PROGMEM = {
|
||||
0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
|
||||
0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
|
||||
0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
|
||||
0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
|
||||
0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
|
||||
0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
|
||||
0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
|
||||
0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
|
||||
0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
|
||||
0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
|
||||
0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
|
||||
0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
|
||||
0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
|
||||
0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
|
||||
0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
|
||||
0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
|
||||
0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
|
||||
0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
|
||||
0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
|
||||
0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
|
||||
0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
|
||||
0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
|
||||
0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
|
||||
0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
|
||||
0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
|
||||
0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
|
||||
0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
|
||||
0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
|
||||
0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
|
||||
0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
|
||||
0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
|
||||
0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78,
|
||||
};
|
||||
|
|
@ -0,0 +1,18 @@
|
|||
// CRC-CCIT Implementation based on work by Francesco Sacchi
|
||||
|
||||
#ifndef CRC_CCIT_H
|
||||
#define CRC_CCIT_H
|
||||
|
||||
#include <stdint.h>
|
||||
#include <avr/pgmspace.h>
|
||||
|
||||
#define CRC_CCIT_INIT_VAL ((uint16_t)0xFFFF)
|
||||
|
||||
extern const uint16_t crc_ccit_table[256];
|
||||
|
||||
inline uint16_t update_crc_ccit(uint8_t c, uint16_t prev_crc) {
|
||||
return (prev_crc >> 8) ^ pgm_read_word(&crc_ccit_table[(prev_crc ^ c) & 0xff]);
|
||||
}
|
||||
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,85 @@
|
|||
#ifndef UTIL_FIFO_H
|
||||
#define UTIL_FIFO_H
|
||||
|
||||
#include <stddef.h>
|
||||
#include <util/atomic.h>
|
||||
|
||||
typedef struct FIFOBuffer
|
||||
{
|
||||
unsigned char *begin;
|
||||
unsigned char *end;
|
||||
unsigned char * volatile head;
|
||||
unsigned char * volatile tail;
|
||||
} FIFOBuffer;
|
||||
|
||||
inline bool fifo_isempty(const FIFOBuffer *f) {
|
||||
return f->head == f->tail;
|
||||
}
|
||||
|
||||
inline bool fifo_isfull(const FIFOBuffer *f) {
|
||||
return ((f->head == f->begin) && (f->tail == f->end)) || (f->tail == f->head - 1);
|
||||
}
|
||||
|
||||
inline void fifo_push(FIFOBuffer *f, unsigned char c) {
|
||||
*(f->tail) = c;
|
||||
|
||||
if (f->tail == f->end) {
|
||||
f->tail = f->begin;
|
||||
} else {
|
||||
f->tail++;
|
||||
}
|
||||
}
|
||||
|
||||
inline unsigned char fifo_pop(FIFOBuffer *f) {
|
||||
if(f->head == f->end) {
|
||||
f->head = f->begin;
|
||||
return *(f->end);
|
||||
} else {
|
||||
return *(f->head++);
|
||||
}
|
||||
}
|
||||
|
||||
inline void fifo_flush(FIFOBuffer *f) {
|
||||
f->head = f->tail;
|
||||
}
|
||||
|
||||
inline bool fifo_isempty_locked(const FIFOBuffer *f) {
|
||||
bool result;
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
result = fifo_isempty(f);
|
||||
}
|
||||
return result;
|
||||
}
|
||||
|
||||
inline bool fifo_isfull_locked(const FIFOBuffer *f) {
|
||||
bool result;
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
result = fifo_isfull(f);
|
||||
}
|
||||
return result;
|
||||
}
|
||||
|
||||
inline void fifo_push_locked(FIFOBuffer *f, unsigned char c) {
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
fifo_push(f, c);
|
||||
}
|
||||
}
|
||||
|
||||
inline unsigned char fifo_pop_locked(FIFOBuffer *f) {
|
||||
unsigned char c;
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
c = fifo_pop(f);
|
||||
}
|
||||
return c;
|
||||
}
|
||||
|
||||
inline void fifo_init(FIFOBuffer *f, unsigned char *buffer, size_t size) {
|
||||
f->head = f->tail = f->begin = buffer;
|
||||
f->end = buffer + size -1;
|
||||
}
|
||||
|
||||
inline size_t fifo_len(FIFOBuffer *f) {
|
||||
return f->end - f->begin;
|
||||
}
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,8 @@
|
|||
#ifndef PROTOCOL_HDLC_H
|
||||
#define PROTOCOL_HDLC_H
|
||||
|
||||
#define HDLC_FLAG 0x7E
|
||||
#define HDLC_RESET 0x7F
|
||||
#define AX25_ESC 0x1B
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,309 @@
|
|||
#include "Arduino.h"
|
||||
#include "AFSK.h"
|
||||
#include "AX25.h"
|
||||
|
||||
Afsk modem;
|
||||
AX25Ctx AX25;
|
||||
extern void aprs_msg_callback(struct AX25Msg *msg);
|
||||
#define countof(a) sizeof(a)/sizeof(a[0])
|
||||
|
||||
unsigned long custom_preamble = 350UL;
|
||||
unsigned long custom_tail = 50UL;
|
||||
|
||||
AX25Call src;
|
||||
AX25Call dst;
|
||||
AX25Call path1;
|
||||
AX25Call path2;
|
||||
|
||||
char CALL[7] = "NOCALL";
|
||||
int CALL_SSID = 0;
|
||||
char DST[7] = "APZMDM";
|
||||
int DST_SSID = 0;
|
||||
char PATH1[7] = "WIDE1";
|
||||
int PATH1_SSID = 1;
|
||||
char PATH2[7] = "WIDE2";
|
||||
int PATH2_SSID = 2;
|
||||
|
||||
AX25Call path[4];
|
||||
|
||||
// Location packet assembly fields
|
||||
char latitude[9];
|
||||
char longtitude[10];
|
||||
char symbolTable = '/';
|
||||
char symbol = 'n';
|
||||
|
||||
uint8_t power = 10;
|
||||
uint8_t height = 10;
|
||||
uint8_t gain = 10;
|
||||
uint8_t directivity = 10;
|
||||
/////////////////////////
|
||||
|
||||
// Message packet assembly fields
|
||||
char message_recip[7];
|
||||
int message_recip_ssid = -1;
|
||||
|
||||
int message_seq = 0;
|
||||
char lastMessage[67];
|
||||
size_t lastMessageLen;
|
||||
bool message_autoAck = false;
|
||||
/////////////////////////
|
||||
|
||||
void APRS_init(void) {
|
||||
AFSK_init(&modem);
|
||||
ax25_init(&AX25, aprs_msg_callback);
|
||||
}
|
||||
|
||||
void APRS_poll(void) {
|
||||
ax25_poll(&AX25);
|
||||
}
|
||||
|
||||
void APRS_setCallsign(char *call, int ssid) {
|
||||
Serial.println("Setting to: ");
|
||||
memset(CALL, 0, 7);
|
||||
int i = 0;
|
||||
while (i < 6 && call[i] != 0) {
|
||||
CALL[i] = call[i];
|
||||
i++;
|
||||
}
|
||||
CALL_SSID = ssid;
|
||||
}
|
||||
|
||||
void APRS_setDestination(char *call, int ssid) {
|
||||
memset(DST, 0, 7);
|
||||
int i = 0;
|
||||
while (i < 6 && call[i] != 0) {
|
||||
DST[i] = call[i];
|
||||
i++;
|
||||
}
|
||||
DST_SSID = ssid;
|
||||
}
|
||||
|
||||
void APRS_setPath1(char *call, int ssid) {
|
||||
memset(PATH1, 0, 7);
|
||||
int i = 0;
|
||||
while (i < 6 && call[i] != 0) {
|
||||
PATH1[i] = call[i];
|
||||
i++;
|
||||
}
|
||||
PATH1_SSID = ssid;
|
||||
}
|
||||
|
||||
void APRS_setPath2(char *call, int ssid) {
|
||||
memset(PATH2, 0, 7);
|
||||
int i = 0;
|
||||
while (i < 6 && call[i] != 0) {
|
||||
PATH2[i] = call[i];
|
||||
i++;
|
||||
}
|
||||
PATH2_SSID = ssid;
|
||||
}
|
||||
|
||||
void APRS_setMessageDestination(char *call, int ssid) {
|
||||
memset(message_recip, 0, 7);
|
||||
int i = 0;
|
||||
while (i < 6 && call[i] != 0) {
|
||||
message_recip[i] = call[i];
|
||||
i++;
|
||||
}
|
||||
message_recip_ssid = ssid;
|
||||
}
|
||||
|
||||
void APRS_setPreamble(unsigned long pre) {
|
||||
custom_preamble = pre;
|
||||
}
|
||||
|
||||
void APRS_setTail(unsigned long tail) {
|
||||
custom_tail = tail;
|
||||
}
|
||||
|
||||
void APRS_useAlternateSymbolTable(bool use) {
|
||||
if (use) {
|
||||
symbolTable = '\\';
|
||||
} else {
|
||||
symbolTable = '/';
|
||||
}
|
||||
}
|
||||
|
||||
void APRS_setSymbol(char sym) {
|
||||
symbol = sym;
|
||||
}
|
||||
|
||||
void APRS_setLat(char *lat) {
|
||||
memset(latitude, 0, 9);
|
||||
int i = 0;
|
||||
while (i < 8 && lat[i] != 0) {
|
||||
latitude[i] = lat[i];
|
||||
i++;
|
||||
}
|
||||
}
|
||||
|
||||
void APRS_setLon(char *lon) {
|
||||
memset(longtitude, 0, 10);
|
||||
int i = 0;
|
||||
while (i < 9 && lon[i] != 0) {
|
||||
longtitude[i] = lon[i];
|
||||
i++;
|
||||
}
|
||||
}
|
||||
|
||||
void APRS_setPower(int s) {
|
||||
if (s >= 0 && s < 10) {
|
||||
power = s;
|
||||
}
|
||||
}
|
||||
|
||||
void APRS_setHeight(int s) {
|
||||
if (s >= 0 && s < 10) {
|
||||
height = s;
|
||||
}
|
||||
}
|
||||
|
||||
void APRS_setGain(int s) {
|
||||
if (s >= 0 && s < 10) {
|
||||
gain = s;
|
||||
}
|
||||
}
|
||||
|
||||
void APRS_setDirectivity(int s) {
|
||||
if (s >= 0 && s < 10) {
|
||||
directivity = s;
|
||||
}
|
||||
}
|
||||
|
||||
void APRS_printSettings() {
|
||||
Serial.println("LibAPRS Settings:");
|
||||
Serial.print("Callsign: "); Serial.print(CALL); Serial.print("-"); Serial.println(CALL_SSID);
|
||||
Serial.print("Destination: "); Serial.print(DST); Serial.print("-"); Serial.println(DST_SSID);
|
||||
Serial.print("Path1: "); Serial.print(PATH1); Serial.print("-"); Serial.println(PATH1_SSID);
|
||||
Serial.print("Path2: "); Serial.print(PATH2); Serial.print("-"); Serial.println(PATH2_SSID);
|
||||
Serial.print("Message dst: "); if (message_recip[0] == 0) { Serial.println("N/A"); } else { Serial.print(message_recip); Serial.print("-"); Serial.println(message_recip_ssid); }
|
||||
Serial.print("TX Preamble: "); Serial.println(custom_preamble);
|
||||
Serial.print("TX Tail: "); Serial.println(custom_tail);
|
||||
Serial.print("Symbol table: "); if (symbolTable = '/') { Serial.println("Normal"); } else { Serial.println("Alternate"); }
|
||||
Serial.print("Symbol: "); Serial.println(symbol);
|
||||
Serial.print("Power: "); if (power < 10) { Serial.println(power); } else { Serial.println("N/A"); }
|
||||
Serial.print("Height: "); if (height < 10) { Serial.println(height); } else { Serial.println("N/A"); }
|
||||
Serial.print("Gain: "); if (gain < 10) { Serial.println(gain); } else { Serial.println("N/A"); }
|
||||
Serial.print("Directivity: "); if (directivity < 10) { Serial.println(directivity); } else { Serial.println("N/A"); }
|
||||
Serial.print("Latitude: "); if (latitude[0] != 0) { Serial.println(latitude); } else { Serial.println("N/A"); }
|
||||
Serial.print("Longtitude: "); if (longtitude[0] != 0) { Serial.println(longtitude); } else { Serial.println("N/A"); }
|
||||
|
||||
}
|
||||
|
||||
void APRS_sendPkt(void *_buffer, size_t length) {
|
||||
|
||||
uint8_t *buffer = (uint8_t *)_buffer;
|
||||
|
||||
memcpy(dst.call, DST, 6);
|
||||
dst.ssid = DST_SSID;
|
||||
|
||||
memcpy(src.call, CALL, 6);
|
||||
src.ssid = CALL_SSID;
|
||||
|
||||
memcpy(path1.call, PATH1, 6);
|
||||
path1.ssid = PATH1_SSID;
|
||||
|
||||
memcpy(path2.call, PATH2, 6);
|
||||
path2.ssid = PATH2_SSID;
|
||||
|
||||
path[0] = dst;
|
||||
path[1] = src;
|
||||
path[2] = path1;
|
||||
path[3] = path2;
|
||||
|
||||
ax25_sendVia(&AX25, path, countof(path), buffer, length);
|
||||
}
|
||||
|
||||
void APRS_sendLoc(void *_buffer, size_t length) {
|
||||
size_t payloadLength = 20+length;
|
||||
bool usePHG = false;
|
||||
if (power < 10 && height < 10 && gain < 10 && directivity < 9) {
|
||||
usePHG = true;
|
||||
payloadLength += 7;
|
||||
}
|
||||
uint8_t *packet = (uint8_t*)malloc(payloadLength);
|
||||
uint8_t *ptr = packet;
|
||||
packet[0] = '=';
|
||||
packet[9] = symbolTable;
|
||||
packet[19] = symbol;
|
||||
ptr++;
|
||||
memcpy(ptr, latitude, 8);
|
||||
ptr += 9;
|
||||
memcpy(ptr, longtitude, 9);
|
||||
ptr += 10;
|
||||
if (usePHG) {
|
||||
packet[20] = 'P';
|
||||
packet[21] = 'H';
|
||||
packet[22] = 'G';
|
||||
packet[23] = power+48;
|
||||
packet[24] = height+48;
|
||||
packet[25] = gain+48;
|
||||
packet[26] = directivity+48;
|
||||
ptr+=7;
|
||||
}
|
||||
if (length > 0) {
|
||||
uint8_t *buffer = (uint8_t *)_buffer;
|
||||
memcpy(ptr, buffer, length);
|
||||
}
|
||||
|
||||
APRS_sendPkt(packet, payloadLength);
|
||||
free(packet);
|
||||
}
|
||||
|
||||
void APRS_sendMsg(void *_buffer, size_t length) {
|
||||
if (length > 67) length = 67;
|
||||
size_t payloadLength = 11+length+4;
|
||||
|
||||
uint8_t *packet = (uint8_t*)malloc(payloadLength);
|
||||
uint8_t *ptr = packet;
|
||||
packet[0] = ':';
|
||||
int callSize = 6;
|
||||
int count = 0;
|
||||
while (callSize--) {
|
||||
if (message_recip[count] != 0) {
|
||||
packet[1+count] = message_recip[count];
|
||||
count++;
|
||||
}
|
||||
}
|
||||
if (message_recip_ssid != -1) {
|
||||
packet[1+count] = '-'; count++;
|
||||
if (message_recip_ssid < 10) {
|
||||
packet[1+count] = message_recip_ssid+48; count++;
|
||||
} else {
|
||||
packet[1+count] = 49; count++;
|
||||
packet[1+count] = message_recip_ssid-10+48; count++;
|
||||
}
|
||||
}
|
||||
while (count < 9) {
|
||||
packet[1+count] = ' '; count++;
|
||||
}
|
||||
packet[1+count] = ':';
|
||||
ptr += 11;
|
||||
if (length > 0) {
|
||||
uint8_t *buffer = (uint8_t *)_buffer;
|
||||
memcpy(ptr, buffer, length);
|
||||
memcpy(lastMessage, buffer, length);
|
||||
lastMessageLen = length;
|
||||
}
|
||||
|
||||
message_seq++;
|
||||
if (message_seq > 999) message_seq = 0;
|
||||
|
||||
packet[11+length] = '{';
|
||||
int n = message_seq % 10;
|
||||
int d = ((message_seq % 100) - n)/10;
|
||||
int h = (message_seq - d - n) / 100;
|
||||
|
||||
packet[12+length] = h+48;
|
||||
packet[13+length] = d+48;
|
||||
packet[14+length] = n+48;
|
||||
|
||||
APRS_sendPkt(packet, payloadLength);
|
||||
|
||||
free(packet);
|
||||
}
|
||||
|
||||
void APRS_msgRetry() {
|
||||
message_seq--;
|
||||
APRS_sendMsg(lastMessage, lastMessageLen);
|
||||
}
|
||||
|
|
@ -0,0 +1,37 @@
|
|||
#include "Arduino.h"
|
||||
#include <stdint.h>
|
||||
#include <stdbool.h>
|
||||
|
||||
#include "FIFO.h"
|
||||
#include "CRC-CCIT.h"
|
||||
#include "HDLC.h"
|
||||
#include "AFSK.h"
|
||||
#include "AX25.h"
|
||||
|
||||
void APRS_init(void);
|
||||
void APRS_poll(void);
|
||||
|
||||
void APRS_setCallsign(char *call, int ssid);
|
||||
void APRS_setDestination(char *call, int ssid);
|
||||
void APRS_setMessageDestination(char *call, int ssid);
|
||||
void APRS_setPath1(char *call, int ssid);
|
||||
void APRS_setPath2(char *call, int ssid);
|
||||
|
||||
void APRS_setPreamble(unsigned long pre);
|
||||
void APRS_setTail(unsigned long tail);
|
||||
void APRS_useAlternateSymbolTable(bool use);
|
||||
void APRS_setSymbol(char sym);
|
||||
|
||||
void APRS_setLat(char *lat);
|
||||
void APRS_setLon(char *lon);
|
||||
void APRS_setPower(int s);
|
||||
void APRS_setHeight(int s);
|
||||
void APRS_setGain(int s);
|
||||
void APRS_setDirectivity(int s);
|
||||
|
||||
void APRS_sendPkt(void *_buffer, size_t length);
|
||||
void APRS_sendLoc(void *_buffer, size_t length);
|
||||
void APRS_sendMsg(void *_buffer, size_t length);
|
||||
void APRS_msgRetry();
|
||||
|
||||
void APRS_printSettings();
|
||||
20
README.md
20
README.md
|
|
@ -0,0 +1,20 @@
|
|||
LibAPRS
|
||||
==========
|
||||
|
||||
LibAPRS is an Arduino IDE library that makes it easy to send and receive APRS packets with a [MicroModem](http://unsigned.io/micromodem)-compatible modem.
|
||||
|
||||
You can buy a complete modem from [my shop](http://unsigned.io/shop), or you can build one yourself pretty easily. Take a look at the documentation in the [MicroModem](https://github.com/markqvist/MicroModem) repository for information and getting started guides!
|
||||
|
||||
See the example included in the library for info on how to use it!
|
||||
|
||||
## Some features
|
||||
|
||||
- Send and receive AX.25 APRS packets
|
||||
- Full modulation and demodulation in software
|
||||
- Easy configuration of callsign and path settings
|
||||
- Easily process incoming packets
|
||||
- Shorthand functions for sending location updates and messages, so you don't need to manually create the packets
|
||||
- Ability to send raw packets
|
||||
- Support for settings APRS symbols
|
||||
- Support for power/height/gain info in location updates
|
||||
- Can run with open squelch
|
||||
|
|
@ -0,0 +1,6 @@
|
|||
#define m328p 0x01
|
||||
#define m1284p 0x02
|
||||
#define m644p 0x03
|
||||
|
||||
#define REF_3V3 0x01
|
||||
#define REF_5V 0x02
|
||||
|
|
@ -0,0 +1,38 @@
|
|||
#include "constants.h"
|
||||
|
||||
#ifndef DEVICE_CONFIGURATION
|
||||
#define DEVICE_CONFIGURATION
|
||||
|
||||
// CPU settings
|
||||
#ifndef TARGET_CPU
|
||||
#define TARGET_CPU m328p
|
||||
#endif
|
||||
|
||||
#ifndef F_CPU
|
||||
#define F_CPU 16000000
|
||||
#endif
|
||||
|
||||
#ifndef FREQUENCY_CORRECTION
|
||||
#define FREQUENCY_CORRECTION 0
|
||||
#endif
|
||||
|
||||
// ADC settings
|
||||
#define OPEN_SQUELCH false
|
||||
#define ADC_REFERENCE REF_3V3
|
||||
// OR
|
||||
//#define ADC_REFERENCE REF_5V
|
||||
|
||||
// Sampling & timer setup
|
||||
#define CONFIG_AFSK_DAC_SAMPLERATE 9600
|
||||
|
||||
// Port settings
|
||||
#if TARGET_CPU == m328p
|
||||
#define DAC_PORT PORTD
|
||||
#define DAC_DDR DDRD
|
||||
#define LED_PORT PORTB
|
||||
#define LED_DDR DDRB
|
||||
#define ADC_PORT PORTC
|
||||
#define ADC_DDR DDRC
|
||||
#endif
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,92 @@
|
|||
// Include LibAPRS
|
||||
#include <LibAPRS.h>
|
||||
|
||||
// You always need to include this function. It will
|
||||
// get called by the library every time a packet is
|
||||
// received, so you can process incoming packets.
|
||||
void aprs_msg_callback(struct AX25Msg *msg) {
|
||||
Serial.print("Received APRS packet. Data: ");
|
||||
for (int i = 0; i < msg->len; i++) { Serial.write(msg->info[i]); }
|
||||
Serial.println("");
|
||||
}
|
||||
|
||||
void setup() {
|
||||
// Set up serial port
|
||||
Serial.begin(9600);
|
||||
|
||||
// Initialise APRS library - This starts the modem
|
||||
APRS_init();
|
||||
|
||||
// You must at a minimum configure your callsign and SSID
|
||||
APRS_setCallsign("NOCALL", 1);
|
||||
|
||||
// You don't need to set the destination identifier, but
|
||||
// if you want to, this is how you do it:
|
||||
APRS_setDestination("APZMDM", 0);
|
||||
|
||||
// Path parameters are set to sensible values by
|
||||
// default, but this is how you can configure them:
|
||||
APRS_setPath1("WIDE1", 1);
|
||||
APRS_setPath2("WIDE2", 2);
|
||||
|
||||
// You can define preamble and tail like this:
|
||||
APRS_setPreamble(350);
|
||||
APRS_setTail(50);
|
||||
|
||||
// You can use the normal or alternate symbol table:
|
||||
APRS_useAlternateSymbolTable(false);
|
||||
|
||||
// And set what symbol you want to use:
|
||||
APRS_setSymbol('n');
|
||||
|
||||
// We can print out all the settings
|
||||
APRS_printSettings();
|
||||
}
|
||||
|
||||
void locationUpdateExample() {
|
||||
// Let's first set our latitude and longtitude.
|
||||
// These should be in NMEA format!
|
||||
APRS_setLat("5530.80N");
|
||||
APRS_setLon("01143.89E");
|
||||
|
||||
// We can optionally set power/height/gain/directivity
|
||||
// information. These functions accept ranges
|
||||
// from 0 to 10, directivity 0 to 9.
|
||||
// See this site for a calculator:
|
||||
// http://www.aprsfl.net/phgr.php
|
||||
// LibAPRS will only add PHG info if all four variables
|
||||
// are defined!
|
||||
APRS_setPower(2);
|
||||
APRS_setHeight(4);
|
||||
APRS_setGain(7);
|
||||
APRS_setDirectivity(0);
|
||||
|
||||
// We'll define a comment string
|
||||
char *comment = "LibAPRS location update";
|
||||
|
||||
// And send the update
|
||||
APRS_sendLoc(comment, sizeof(comment));
|
||||
|
||||
}
|
||||
|
||||
void messageExample() {
|
||||
// We first need to set the message recipient
|
||||
APRS_setMessageDestination("AA3BBB", 0);
|
||||
|
||||
// And define a string to send
|
||||
char *message = "Hi there! This is a message";
|
||||
APRS_sendMsg(message, sizeof(message));
|
||||
|
||||
}
|
||||
|
||||
void loop() {
|
||||
delay(2000);
|
||||
locationUpdateExample();
|
||||
|
||||
delay(2000);
|
||||
messageExample();
|
||||
|
||||
// Just for fun we print out the settings
|
||||
APRS_printSettings();
|
||||
|
||||
}
|
||||
Ładowanie…
Reference in New Issue