/*
Write a Command to the RFM Module using SPI
Requires: 16bit valid command
Returns: 16bit result from transaction
This is a bi-directional transfer.
A command is clocked out to the RFM a bit at a time.
At the same time a result is clocked back in a bit at a time.
*/
uint WriteCMD(uint CMD)
{
uint RESULT = 0; // Holds the received SDI
uchar n=16; // number of bits in SPI Command we need to send
LOW_SCK(); // SCK LOW
LOW_SEL(); // CS LOW
while(n--) // Send All 16 Bits MSB First
{
if (CMD&0x8000)
{
Write1(); // Write 1 via SDI
}
else
{
Write0(); // Write 0 via SPI
}
RESULT<<=1; // Shift left for next bit to receive
if(SDI) // Check if we received a high on SDI
RESULT |= 0x0001; // RESULT LSB = 1
CMD<<=1; // Shift left for next bit to send
}
LOW_SCK(); // SCK LOW
HI_SEL(); // CS HIGH - Finished Sending Command
return RESULT;
}
uint16_t rfxx_wrt_cmd(uint16_t aCmd) {
uint8_t i;
uint16_t temp = 0;
LOW_SCK();
LOW_SEL();
//for (i=0; i<16; i++) {
for (i = 0; i < sizeof(uint16_t); ++i) {
temp <<= 1;
if (SDO_HI()) temp |= 0x0001;
LOW_SCK();
(aCmd & 0x8000) ? (HI_SDI()) : (LOW_SDI());
/*
if (aCmd & 0x8000)
HI_SDI();
else
LOW_SDI();
*/
HI_SCK();
aCmd <<= 1;
}
LOW_SCK();
HI_SEL();
return temp;
}
void RFXX_PORT_INIT(void) {
HI_SEL();
HI_SDI();
LOW_SCK();
SEL_OUTPUT();
SDI_OUTPUT();
SDO_INPUT();
SCK_OUTPUT();
}
void RFXX_PORT_INIT(void){
HI_SEL();
HI_SDI();
LOW_SCK();
//SET nFFS pin HI when using FIFO
HI_DATA();
SEL_OUTPUT();
SDI_OUTPUT();
SDO_INPUT();
SCK_OUTPUT();
IRQ_IN();
DATA_OUT();
}
void init(void)
{
//osccon = 0x70; // 8Mhz internal OSC
cmcon = 0x07;
//ansel = 0; // all is digital i/o on PortA
option_reg.NOT_RBPU = 0; // enable pullup resistors on PB
option_reg.INTEDG = 0; // falling edge interrupt
CONF_LED1_OUT();
LED1=0;
// setup SPI
// outputs
RFM12_CS_OUT(); // Module Chip Select
HI_SEL(); // RF CS is Active Low so set High
SCK_OUT(); // SPI SCK as Output
LOW_SCK();
SDO_OUT(); // SPI SDO as Output
LOW_SDO();
// inputs
RFM12_nIRQ_IN(); // nIRQ
SDI_IN(); // SPI SDI
delay_ms(500); // Wait for RFM12 POR
WriteCMD(0x80F7); // 915 EL, EF, 12.0pf
WriteCMD(0xA7D0); // 915=A7D0 904.50MHZ = A258
WriteCMD(0xC623); // c608=38400 c611=19200 c623= 9600bps
WriteCMD(0xC22C); // Data Filter: AL, !ML, digital filter, 4 dqd
WriteCMD(0xC4F7); // AFC Autotune, -10khz..+7.5Khz, !st, !fi, OE, EN
WriteCMD(0x96A0); // P16, VDI, FAST, 65khz, 0dBm, -103dBm
WriteCMD(0xCA81); // FIFO8, SYNC, !ff, DR
//TX Config
//WriteCMD(0x9850); // !mp, 9810=30Khz, MAX out
WriteCMD(0xE000); // NOT USE
WriteCMD(0xC80E); // NOT USE
WriteCMD(0xC000); // CLK 1mhz, 2.2v
WriteCMD(0x8280); // ER, EBB, !ET, ES, EX, !EB, !EW, !DC
}
/*
Waits for RFM 12 to become ready by checking first bit of status register
Before we can Tx or Rx data the RFM12 needs to be ready,
i.e. not in the middle of transmitting a previous byte
This function is blocking and will only return when it is ready to Tx or Rx
*/
void WaitReady(void)
{
//#ifdef DEBUG // always return for simulator
// return;
//#endif
unsigned long timeout = 0;
bit READY = 0;
while(READY == 0)
{
LOW_SCK(); // SCK LOW
LOW_SEL(); // CS LOW
Write0();
if(SDI==1) // check RGIT bit of status (first bit)
{ // If HIGH then Tx/RX is ready to accept the next byte
READY = 1;
}
LOW_SCK(); // SCK LOW
LOW_SDO();
HI_SEL(); // CS HIGH - Finished Sending Command
}
}
unsigned int RFXX_WRT_CMD(unsigned int aCmd){
unsigned char i;
unsigned int temp;
temp=0;
LOW_SCK();
LOW_SEL();
for(i=0;i<16;i++){
if(aCmd&0x8000){
HI_SDI();
}else{
LOW_SDI();
}
HI_SCK();
temp<<=1;
if(SDO_HI()){
temp|=0x0001;
}
LOW_SCK();
aCmd<<=1;
};
HI_SEL();
return(temp);
}
