/***************************************************************************
Declaration : char get_sync(void)
Description : The Slave synchronizes to the Master frame by resetting the
frame timer when a valid packet is received.
***************************************************************************/
char get_sync(void)
{
char status;
char sync_counter = 0;
int i;
// Receive until valid packet or timeout
while(1)
{
for(i=0; i<N_FREQ_CONNECTED; i++)
{
set_rf_rx(freq[i]);
clear_rf_interrupt();
RF_ENABLE;
status = wait_rf_irq(TIMEOUT_SYNC,DIV64);
RF_DISABLE;
if(status == STATUS_TIMEOUT)
{
// Increment sync attempt counter
sync_counter += 1;
if(sync_counter >= N_SYNC_ATTEMPTS)
return(call_status & ~MASTER_SYNC);
}
else
{
SET_TIMER1((master_sync_times[i]+SYNC_DELAY));
return(call_status | MASTER_SYNC);
}
}
}
}
void CCP1_ISR(void){
if (echo == 1){
SETUP_CCP1(CCP_CAPTURE_FE);
SET_TIMER1(0);
echo = 0;
}
else{
SETUP_CCP1(CCP_CAPTURE_RE);
value = CCP_1;
echo = 1;
}
}
/***************************************************************************
Declaration : void audio_transfer(void)
Description : Writes an audio payload to the radio and exchanges audio
payloads at the given frequencies. Reads the audio payload
from the radio if any is received.
***************************************************************************/
void audio_transfer(void)
{
char status[2];
int i;
#ifdef DONGLE
// Exchange Audio Packets at each frequency
event_time = &event_times[0];
for(i=0; i<N_FREQ_CONNECTED; i++)
{
// Send TX packet synchronized to frame
set_rf_tx(freq[i]);
clear_rf_interrupt();
#ifdef USB
SET_TIMER2_EVENT((char)*event_time++);
while(!TIMER2_EVENT)
;
#else
SET_TIMER1_EVENT(*event_time++);
while(!TIMER1_EVENT)
;
#endif
rf_enable_pulse();
wait_rf_irq(TIMEOUT_AUDIO_PACKET,DIV8);
// Receive Audio RX packet
set_rf_rx(freq[i]);
clear_rf_interrupt();
RF_ENABLE;
#ifdef USB
SET_TIMER2_EVENT((char)*event_time++);
while(!TIMER2_EVENT)
;
#else
SET_TIMER1_EVENT(*event_time++);
while(!TIMER1_EVENT)
;
#endif
if(!nRF_IRQ)
status[i] = STATUS_RX_OK;
else
status[i] = STATUS_RX_FAILED;
RF_DISABLE;
}
#ifdef USB
STOP_TIMER2;
#endif
// Read RX Audio Packet if any, else stuff a packet
if((status[0] == STATUS_RX_OK) || (status[1] == STATUS_RX_OK))
{
get_audio_packet();
frame_loss = 0;
}
else
{
// Set Signal
stuff_packet();
frame_loss += 1;
}
// Flush RX FIFO
flush_rf_rx();
// Update Packet Loss counters
if((signal_in[0] & SIGNAL_PACKET0_OK) && (status[0] == STATUS_RX_OK))
{
packet_loss[0] -= PACKET_LOSS_DECREMENT;
if(packet_loss[0] < 0)
packet_loss[0] = 0;
}
else
packet_loss[0] += PACKET_LOSS_INCREMENT;
if((signal_in[0] & SIGNAL_PACKET1_OK) && (status[1] == STATUS_RX_OK))
{
packet_loss[1] -= PACKET_LOSS_DECREMENT;
if(packet_loss[1] < 0)
packet_loss[1] = 0;
}
else
packet_loss[1] += PACKET_LOSS_INCREMENT;
// Change Frequency based on Packet Loss Statistics
if(packet_loss[0] >= PACKET_LOSS_THRESHOLD)
{
freq[0] += FREQ_STEP;
if(freq[0] > FREQ0_MAX)
freq[0] -= (FREQ0_MAX - FREQ0_MIN);
packet_loss[0] = 0;
packet_loss[1] = 0;
}
if(packet_loss[1] >= PACKET_LOSS_THRESHOLD)
{
freq[1] += FREQ_STEP;
if(freq[1] > FREQ1_MAX)
freq[1] -= (FREQ1_MAX - FREQ1_MIN);
packet_loss[0] = 0;
packet_loss[1] = 0;
}
signal_out[1] = freq[1] - freq[0];
//Write TX Audio Packet and enable payload re-use
put_audio_packet();
reuse_rf_payload();
#endif
#ifdef HEADSET
// Exchange Audio Packets at each frequency
event_time = &event_times[0];
SET_TIMER1_EVENT(*event_time++);
for(i=0; i<N_FREQ_CONNECTED; i++)
{
// Receive Audio RX packet
set_rf_rx(freq[i]);
clear_rf_interrupt();
while(!TIMER1_EVENT)
;
RF_ENABLE;
SET_TIMER1_EVENT(*event_time++);
while(!TIMER1_EVENT && nRF_IRQ)
//while(!TIMER1_EVENT)
;
// If RF Interrupt request, RX OK
if(!nRF_IRQ)
{
status[i] = STATUS_RX_OK;
SET_TIMER1(master_sync_times[i]);
}
else
status[i] = STATUS_RX_FAILED;
RF_DISABLE;
// Send Audio TX packet
set_rf_tx(freq[i]);
clear_rf_interrupt();
SET_TIMER1_EVENT(*event_time++);
while(!TIMER1_EVENT)
;
rf_enable_pulse();
SET_TIMER1_EVENT(*event_time++);
wait_rf_irq(TIMEOUT_AUDIO_PACKET,DIV8);
}
// Read RX Audio Packet if any, else stuff a packet
if((status[0] == STATUS_RX_OK) || (status[1] == STATUS_RX_OK))
{
get_audio_packet();
frame_loss = 0;
}
else
{
stuff_packet();
signal_in[0] &= ~SIGNAL_CALL_CLEAR;
frame_loss += 1;
}
// Flush RX FIFO
flush_rf_rx();
// Set Receive Status bits and update Frequency
if(status[0] == STATUS_RX_OK)
{
signal_out[0] |= SIGNAL_PACKET0_OK;
if(status[1] == STATUS_RX_OK)
signal_out[0] |= SIGNAL_PACKET1_OK;
else
{
signal_out[0] &= ~SIGNAL_PACKET1_OK;
freq[1] = freq[0] + signal_in[1];
}
}
else
{
signal_out[0] &= ~SIGNAL_PACKET0_OK;
if(status[1] == STATUS_RX_OK)
{
signal_out[0] |= SIGNAL_PACKET1_OK;
freq[0] = freq[1] - signal_in[1];
}
else
signal_out[0] &= ~SIGNAL_PACKET1_OK;
}
// Write TX Audio Packet and enable payload re-use
put_audio_packet();
reuse_rf_payload();
#endif
}
