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Direct serial line in/out. P-persistent CSMA. SLIP compatibility.

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This commit is contained in:
Mark Qvist 2014-04-27 18:54:01 +02:00
parent 74542aa87a
commit bd11c5ee83
9 changed files with 180 additions and 52 deletions
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14
Modem/hardware.c
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@ -111,8 +111,10 @@ void hw_afsk_adcInit(int ch, Afsk *_modem)
// "ADC_vect". This lets the processor know what to do
// when all the timing and configuration we just set up
// finally* ends up triggering the interrupt.
bool hw_ptt_on;
bool hw_afsk_dac_isr;
DECLARE_ISR(ADC_vect) {
TIFR1 = BV(ICF1);
// Call the routine for analysing the captured sample
@ -131,7 +133,7 @@ DECLARE_ISR(ADC_vect) {
// We also need to check if we're supposed to spit
// out some modulated data to the DAC.
if (hw_afsk_dac_isr)
if (hw_afsk_dac_isr) {
// If there is, it's easy to actually do so. We
// calculate what the sample should be in the
// DAC ISR, and apply the bitmask 11110000. This
@ -143,12 +145,18 @@ DECLARE_ISR(ADC_vect) {
// by the PORTD register. This is the PTT pin
// which tells the radio to open it transmitter.
PORTD = (afsk_dac_isr(modem) & 0xF0) | BV(3);
else
} else {
// If we're not supposed to transmit anything, we
// keep quiet by continously sending 128, which
// when converted to an AC waveform by the DAC,
// equates to a steady, unchanging 0 volts.
PORTD = 128;
if (hw_ptt_on) {
PORTD = 136;
} else {
PORTD = 128;
}
}
}