char SetupCC1020RX(char RXANALOG1, char PA_POWER1)
{
volatile int TimeOutCounter;
char lock_status;
// Turn ON DCLK_CS (Carrier Sense Squelch) in RX
WriteToCC1020Register(CC1020_INTERFACE,ReadFromCC1020Register(CC1020_INTERFACE) | 0x10);
// Switch into RX, switch to freq. reg A
WriteToCC1020Register(CC1020_MAIN,0x11);
// Setup bias current adjustment
WriteToCC1020Register(CC1020_ANALOG,RXANALOG);
// Monitor LOCK
for(TimeOutCounter=30; ((ReadFromCC1020Register(CC1020_STATUS)&0x10)==0)&&(TimeOutCounter>0); TimeOutCounter--)
{
_delay_ms(1);
}
// If PLL in lock
if((ReadFromCC1020Register(CC1020_STATUS)&0x10)==0x10)
{
lock_status = TRUE;
sbi(PORTA,LED_PLL);
}
else // Recalibrate
{
// If recalibration ok
if(CalibrateCC1020(PA_POWER1))
{
lock_status = TRUE;
sbi(PORTA,LED_PLL);
// Else (recalibration failed)
}
else
{
lock_status = FALSE;
cbi(PORTA,LED_PLL);
}
}
// Switch RX part of CC1020 on // RX coming out of PD at this stage
WriteToCC1020Register(CC1020_MAIN,0x01);
// Configure LOCK pin to continuous lock status. Active low indicates PLL in lock
//WriteToCC1020Register(CC1020_LOCK,0x20);
// Configure LOCK pin to indicate carrier sense. Active low when RSSI above threshold
WriteToCC1020Register(CC1020_LOCK,0x40);
// Return LOCK status to application
return (lock_status);
}
char SetupCC1020TX(char TXANALOG1, char PA_POWER1)
{
volatile int TimeOutCounter;
int lock_status;
// Turn off PA to avoid frequency splatter
WriteToCC1020Register(CC1020_PA_POWER,0x00);
// Setup bias current adjustment
WriteToCC1020Register(CC1020_ANALOG,TXANALOG1);
// Switch into TX, switch to freq. reg B
WriteToCC1020Register(CC1020_MAIN,0xC1); // TX Coming out of Power down at this stage
// Monitor lock
// LOCK_CONTINUOUS bit set to 1 when PLL is in LOCK
for(TimeOutCounter=30; ((ReadFromCC1020Register(CC1020_STATUS)&0x10)==0x00)&&(TimeOutCounter>0); TimeOutCounter--)
{
_delay_ms(1);
}
// If PLL in lock
if((ReadFromCC1020Register(CC1020_STATUS)&0x10)==0x10)
{
lock_status = TRUE;
sbi(PORTA,LED_PLL);
}
else // if PLL is not locked then Recalibrate
{
// If recalibration ok
if(CalibrateCC1020(PA_POWER1))
{
lock_status = TRUE;
sbi(PORTA,LED_PLL);
// Else (recalibration failed)
}
else
{
lock_status = FALSE;
cbi(PORTA,LED_PLL);
}
}
// Restore PA setting
WriteToCC1020Register(CC1020_PA_POWER,PA_POWER1);
// Turn OFF DCLK_CS (Carrier Sense Squelch) in TX
WriteToCC1020Register(CC1020_INTERFACE,ReadFromCC1020Register(CC1020_INTERFACE)&~0x10);
// Configure LOCK pin to continuous lock status. Active low indicates PLL in lock
WriteToCC1020Register(CC1020_LOCK,0x20);
// Return LOCK status to application
return (lock_status);
}
void WakeUpCC1020ToRX(char RXANALOG1)
{
// Turn on xtal oscillator core
WriteToCC1020Register(CC1020_MAIN,0x1B);
// Setup bias current adjustment
WriteToCC1020Register(CC1020_ANALOG,RXANALOG1);
// Insert wait routine here, must wait for xtal oscillator to stabilise,
// typically takes 2-5ms.
//for (i=0x0260; i > 0; i--);
_delay_ms(3);
// Turn on bias generator
WriteToCC1020Register(CC1020_MAIN,0x19);
x = ReadFromCC1020Register(CC1020_MAIN);
sprintf(arr, "Read: %x\r\n", x);
//send_UART(arr, strlen(arr));
// Wait for 150 usec
_delay_us(150);
// Turn on frequency synthesiser
WriteToCC1020Register(CC1020_MAIN,0x11);
}
int CalibrateCC1020(char PA_POWER1)
{
volatile int TimeOutCounter;
volatile int nCalAttempt;
// Turn off PA to avoid spurs during calibration in TX mode
WriteToCC1020Register(CC1020_PA_POWER,0x00);
// Calibrate, and re-calibrate if necessary:
for (nCalAttempt = CAL_ATTEMPT_MAX; (nCalAttempt>0); nCalAttempt--)
{
// Start calibration
WriteToCC1020Register(CC1020_CALIBRATE,0xB4); // verified with cc1020 datasheet
// Wait for 100 usec. As given errata notes.
for (int i=0x000B; i > 0; i--);
// Monitor calibration complete bit in STATUS register
// CAL_COMPLETE bit set to 1 when calibration is complete
// Waiting time according to register settings is approx 27ms. Ref_freq=fosc/2 and CAL_WAIT = 11
// We are waiting for 30ms
for(TimeOutCounter=30; ((ReadFromCC1020Register(CC1020_STATUS)&0x80)==0x00)&&(TimeOutCounter>0); TimeOutCounter--)
{
_delay_ms(1);
}
// Monitor lock
// LOCK_CONTINUOUS bit in STATUS register is set to 1 when PLL is in LOCK
for(TimeOutCounter=30; ((ReadFromCC1020Register(CC1020_STATUS)&0x10)==0x00)&&(TimeOutCounter>0); TimeOutCounter--)
{
_delay_ms(1);
}
// Abort further recalibration attempts if successful LOCK
if((ReadFromCC1020Register(CC1020_STATUS)&0x10) == 0x10)
{
break;
}
}
// Restore PA setting
WriteToCC1020Register(CC1020_PA_POWER, PA_POWER1);
// Return state of LOCK_CONTINUOUS bit
return ((ReadFromCC1020Register(CC1020_STATUS)&0x10)==0x10);
}
void SetupCC1020PD(void)
{
// Put CC1020 into power-down
WriteToCC1020Register(CC1020_MAIN,0x1F);
x = ReadFromCC1020Register(CC1020_MAIN);
sprintf(arr, "Read: %x\r\n", x);
//send_UART(arr, strlen(arr));
// Turn off PA to minimise current draw
WriteToCC1020Register(CC1020_PA_POWER,0x00);
}
void SetupCC1020PD(void)
{
uint8_t x;
char bufff[100];
// Put CC1020 into power-down
WriteToCC1020Register(CC1020_MAIN,0x1F);
x = ReadFromCC1020Register(CC1020_MAIN);
sprintf(bufff,"Wake up complete : %d a\r\n",x);
usart_transmit(bufff);
// Turn off PA to minimise current draw
WriteToCC1020Register(CC1020_PA_POWER,0x00);
}
int ReadRSSIlevelCC1020(void)
{
char i;
//unsigned char RSSI[5];
unsigned char FILTER;
int RSSI_dBm;
// RSSI formula based on CC1020 datahseet and application note 30:
// P = 1.5 x RSSI - 3 x VGA_SETTING - RSSI_Offset [dBm]
/*
VGA_SETTING based on SmartRF Studio - CC1020, v5.3.0.0
Note: these settings could be subject to optimisation.
434MHz range:
-------------------------------------------------
12.5 => VGA3 = 0x31 => VGA_SETTING = 0x11 = 17dec
25 => VGA3 = 0x2F => VGA_SETTING = 0x0F = 15dec
50 => VGA3 = 0x2E => VGA_SETTING = 0x0E = 14dec
100 => VGA3 = 0x2D => VGA_SETTING = 0x0D = 13dec
150 => VGA3 = 0x2F => VGA_SETTING = 0x0F = 15dec
200 => VGA3 = 0x32 => VGA_SETTING = 0x12 = 18dec
500 => VGA3 = 0x33 => VGA_SETTING = 0x13 = 19dec
868MHz range:
-------------------------------------------------
12.5 => VGA3 = 0x2F => VGA_SETTING = 0x0F = 15dec
25 => VGA3 = 0x2E => VGA_SETTING = 0x0E = 14dec
50 => VGA3 = 0x2D => VGA_SETTING = 0x0D = 13dec
100 => VGA3 = 0x2D => VGA_SETTING = 0x0D = 13dec
150 => VGA3 = 0x2E => VGA_SETTING = 0x0E = 14dec
200 => VGA3 = 0x30 => VGA_SETTING = 0x10 = 16dec
500 => VGA3 = 0x34 => VGA_SETTING = 0x14 = 20dec
*/
// Get current channel spacing
FILTER = ReadFromCC1020Register(CC1020_FILTER)&0x7F;
// Calculate average RSSI in dBm (initially without offset):
//for(i = 0; i < 5; i++) {
// RSSI[i] = ReadFromCC1020Register(CC1020_RSSI);
//}
//RSSI_dBm = (int)((((unsigned int)RSSI[0]+(unsigned int)RSSI[1]+(unsigned int)RSSI[2]+(unsigned int)RSSI[3]+(unsigned int)RSSI[4])*3)/(2*5));
RSSI_dBm = RXBUFFER[0];
RSSI_dBm = ((RSSI_dBm*3) - (3*(int)(ReadFromCC1020Register(CC1020_VGA3)&0x1F)*2)) / 2; // RSSI w/o offset
// Calculate average RSSI in dBm with offset, according to frequency band:
// Active frequency is in 800 MHz band
if( (ReadFromCC1020Register(CC1020_ANALOG)&0x80) == 0x80 )
{
switch ( FILTER )
{
case 0x58://12.5 kHz spacing
case 0x3F://12.5 kHz spacing, optimal sensitivity
RSSI_dBm = RSSI_dBm - 95;
break;
case 0x2F://25 kHz spacing
RSSI_dBm = RSSI_dBm - 96;
break;
case 0x2B://50 kHz spacing
RSSI_dBm = RSSI_dBm - 95;
break;
case 0x25://100 kHz spacing
RSSI_dBm = RSSI_dBm - 96;
break;
case 0x22://150 kHz spacing
RSSI_dBm = RSSI_dBm - 99;
break;
case 0x01://200 kHz spacing
RSSI_dBm = RSSI_dBm - 99;
break;
case 0x00://500 kHz spacing
RSSI_dBm = RSSI_dBm - 101;
break;
}
// Active frequency is in 434 MHz band
}
else
{
switch ( FILTER ) {
case 0x38://12.5 kHz spacing
case 0x2F://25 kHz spacing
RSSI_dBm = RSSI_dBm - 102;
break;
case 0x2B://50 kHz spacing
RSSI_dBm = RSSI_dBm - 100;
break;
case 0x25://100 kHz spacing
RSSI_dBm = RSSI_dBm - 99;
break;
case 0x22://150 kHz spacing
RSSI_dBm = RSSI_dBm - 101;
break;
case 0x01://200 kHz spacing
RSSI_dBm = RSSI_dBm - 102;
break;
case 0x00://500 kHz spacing
RSSI_dBm = RSSI_dBm - 103;
break;
}
}
return(RSSI_dBm);
}
int Receivepacket(void)
{
unsigned char dummy=0x00;
// unsigned char reg=0x00;
char prev_bit=1;
char Preamblefound=0, SOF=0, err_flag=0;
curr_buffer_index=0;
no_databytes_toread=0;
rxcount=0;
RXBUFFER[curr_buffer_index]=ReadFromCC1020Register(CC1020_RSSI); //RXBUFFER[0]=RSSI
curr_buffer_index++;
RXBUFFER[curr_buffer_index]=ReadFromCC1020Register(CC1020_STATUS); //RXBUFFER[1]=STATUS
curr_buffer_index++;
// Detect preamble.
while(!Preamblefound)
{
// Read first bit
while (PINB&(1<<DCLK)); // read data on rising edge of DCLK
while (!(PINB&(1<<DCLK))); // since by then it is stable
//_delay_us(100);
if(PINB & (1<<DIO)) // Is the first bit 1?
{
if(prev_bit==0) // 01 found, increment count
rxcount=rxcount+2;
else
rxcount=0;
}
else
{
// No, first bit is 0. Next read second bit
while (PINB&(1<<DCLK));
while (!(PINB&(1<<DCLK)));
//_delay_us(100);
if(PINB & (1<<DIO)) // Is 2nd bit 1?
{
prev_bit=1;
rxcount=rxcount+2; // 01 found, increment count
}
else
{
prev_bit=0;
rxcount=0;
}
}
//if(rxcount==40) // 5 bytes of preamble received. This is value is changeable.
if(rxcount==56) // 7 bytes of preamble received. This is value is changeable.
//if(rxcount==72) // 9 bytes
{
Preamblefound=1;
}
}
// Detect Start of Frame (SOF)
/*while(!SOF)
{
dummy=0x00;
for(int l=1;l<=4;l++) // Read 4 bits.
{
while (PINB&(1<<DCLK));
while (!(PINB&(1<<DCLK)));
//_delay_us(100);
dummy=dummy<<1;
if(PINB & (1<<DIO))
{dummy |= 0x01;}
else dummy &= 0xFE;
}
switch(dummy)
{
case 0x00: //error
err_flag=1;
break;
case 0x01: //error
err_flag=1;
break;
case 0x02: //error
err_flag=1;
break;
case 0x03: //error
err_flag=1;
break;
case 0x04: //error
err_flag=1;
break;
case 0x05: // Part of remaining preamble. Just increment count, do nothing
rxcount=rxcount+2;
break;
case 0x06: //error
err_flag=1;
break;
case 0x07: //Start of frame detetcted
SOF=1;
for(int l=5;l<=8;l++) // Read the remaining 4 bits
{
while (PINB&(1<<DCLK));
while (!(PINB&(1<<DCLK)));
//_delay_us(100);
dummy=dummy<<1;
if(PINB & (1<<DIO))
{dummy |= 0x01;}
else dummy &= 0xFE;
}
RXBUFFER[curr_buffer_index]=rxcount; //RXBUFFER[2]=No. of bits of preamble received.
curr_buffer_index++;
RXBUFFER[curr_buffer_index]=dummy; //RXBUFFER[3]=SOF_1 / flag
curr_buffer_index++;
/*ReadNumberofBytes(2); //RXBUFFER[4]=SOF_2 & RXBUFFER[5]=Number of Data bytes to read
curr_buffer_index--;
no_databytes_toread = RXBUFFER[curr_buffer_index];
curr_buffer_index++;*/
/*ReadNumberofBytes(1);
curr_buffer_index--;
curr_byte = RXBUFFER[curr_buffer_index];
curr_buffer_index++;
//if((RXBUFFER[3] != SOF_1) || (RXBUFFER[4] != SOF_2))
if((RXBUFFER[3] != flag))
{
//SOF is not correctly received
err_flag=1;
}
break;
}
if(err_flag==1)
{
return(0);
}
}*/
while(!SOF)
{
dummy=0x00;
for(int l=1; l<=8; l++) // Read 8 bits.
{
while (PINB&(1<<DCLK));
while (!(PINB&(1<<DCLK)));
//_delay_us(100);
dummy=dummy<<1;
if(PINB & (1<<DIO))
{
dummy |= 0x01;
}
else dummy &= 0xFE;
}
while (dummy != flag)
{
while (PINB&(1<<DCLK));
while (!(PINB&(1<<DCLK)));
//_delay_us(100);
dummy=dummy<<1;
if(PINB & (1<<DIO))
{
dummy |= 0x01;
}
else dummy &= 0xFE;
}
SOF = 1;
RXBUFFER[curr_buffer_index]=rxcount; //RXBUFFER[2]=No. of bits of preamble received.
curr_buffer_index++;
RXBUFFER[curr_buffer_index]=dummy; //RXBUFFER[3]=SOF_1 / flag
curr_buffer_index++;
/*ReadNumberofBytes(2); //RXBUFFER[4]=SOF_2 & RXBUFFER[5]=Number of Data bytes to read
curr_buffer_index--;
no_databytes_toread = RXBUFFER[curr_buffer_index];
curr_buffer_index++;*/
ReadNumberofBytes(1);
curr_buffer_index--;
curr_byte = RXBUFFER[curr_buffer_index];
curr_buffer_index++;
//if((RXBUFFER[3] != SOF_1) || (RXBUFFER[4] != SOF_2))
if((RXBUFFER[3] != flag))
{
//SOF is not correctly received
err_flag=1;
//return(0);
}
}
if(err_flag==1)
{
return(0);
}
//ReadNumberofBytes(no_databytes_toread);
while (curr_byte != flag)
{
ReadNumberofBytes(1);
curr_buffer_index--;
curr_byte = RXBUFFER[curr_buffer_index];
curr_buffer_index++;
}
return(rxcount);
}
