Cooper Liu / RFSRF05

RF12B.cpp@0:1e4910aeb884, 2012-03-14 (annotated)

Committer:
xiaxia686
Date:
Wed Mar 14 17:05:15 2012 +0000
Revision:
0:1e4910aeb884
RF + SRF05 libray

Who changed what in which revision?

UserRevisionLine numberNew contents of line
xiaxia686 0:1e4910aeb884 1 #include "RF12B.h"
xiaxia686 0:1e4910aeb884 2
xiaxia686 0:1e4910aeb884 3 #include "RF_defs.h"
xiaxia686 0:1e4910aeb884 4 #include <algorithm>
xiaxia686 0:1e4910aeb884 5
xiaxia686 0:1e4910aeb884 6
xiaxia686 0:1e4910aeb884 7 RF12B::RF12B(PinName _SDI,
xiaxia686 0:1e4910aeb884 8 PinName _SDO,
xiaxia686 0:1e4910aeb884 9 PinName _SCK,
xiaxia686 0:1e4910aeb884 10 PinName _NCS,
xiaxia686 0:1e4910aeb884 11 PinName _NIRQ):spi(_SDI, _SDO, _SCK),
xiaxia686 0:1e4910aeb884 12 NCS(_NCS), NIRQ(_NIRQ), NIRQ_in(_NIRQ), rfled(LED3) {
xiaxia686 0:1e4910aeb884 13
xiaxia686 0:1e4910aeb884 14 /* SPI frequency, word lenght, polarity and phase */
xiaxia686 0:1e4910aeb884 15 spi.format(16,0);
xiaxia686 0:1e4910aeb884 16 spi.frequency(2000000);
xiaxia686 0:1e4910aeb884 17
xiaxia686 0:1e4910aeb884 18 /* Set ~CS high */
xiaxia686 0:1e4910aeb884 19 NCS = 1;
xiaxia686 0:1e4910aeb884 20
xiaxia686 0:1e4910aeb884 21 /* Initialise RF Module */
xiaxia686 0:1e4910aeb884 22 init();
xiaxia686 0:1e4910aeb884 23
xiaxia686 0:1e4910aeb884 24 /* Setup interrupt to happen on falling edge of NIRQ */
xiaxia686 0:1e4910aeb884 25 NIRQ.fall(this, &RF12B::rxISR);
xiaxia686 0:1e4910aeb884 26 }
xiaxia686 0:1e4910aeb884 27
xiaxia686 0:1e4910aeb884 28 /* Returns the packet length if data is available in the receive buffer, 0 otherwise*/
xiaxia686 0:1e4910aeb884 29 unsigned int RF12B::available() {
xiaxia686 0:1e4910aeb884 30 return fifo.size();
xiaxia686 0:1e4910aeb884 31 }
xiaxia686 0:1e4910aeb884 32
xiaxia686 0:1e4910aeb884 33 /* Reads a packet of data, with length "size" Returns false if read failed. TODO: make a metafifo to isolate packets*/
xiaxia686 0:1e4910aeb884 34 bool RF12B::read(unsigned char* data, unsigned int size) {
xiaxia686 0:1e4910aeb884 35 if (fifo.size() == 0) {
xiaxia686 0:1e4910aeb884 36 return false;
xiaxia686 0:1e4910aeb884 37 } else {
xiaxia686 0:1e4910aeb884 38 unsigned int i = 0;
xiaxia686 0:1e4910aeb884 39 while (fifo.size() > 0 && i < size) {
xiaxia686 0:1e4910aeb884 40 data[i++] = fifo.front();
xiaxia686 0:1e4910aeb884 41 fifo.pop();
xiaxia686 0:1e4910aeb884 42 }
xiaxia686 0:1e4910aeb884 43 return true;
xiaxia686 0:1e4910aeb884 44 }
xiaxia686 0:1e4910aeb884 45 }
xiaxia686 0:1e4910aeb884 46
xiaxia686 0:1e4910aeb884 47 /* Reads a byte of data from the receive buffer */
xiaxia686 0:1e4910aeb884 48 unsigned char RF12B::read() {
xiaxia686 0:1e4910aeb884 49 if (available()) {
xiaxia686 0:1e4910aeb884 50 unsigned char data = fifo.front();
xiaxia686 0:1e4910aeb884 51 fifo.pop();
xiaxia686 0:1e4910aeb884 52 return data;
xiaxia686 0:1e4910aeb884 53 } else {
xiaxia686 0:1e4910aeb884 54 return 0xFF; // Error val although could also be data...
xiaxia686 0:1e4910aeb884 55 }
xiaxia686 0:1e4910aeb884 56 }
xiaxia686 0:1e4910aeb884 57
xiaxia686 0:1e4910aeb884 58 /* Sends a packet of data to the RF module for transmission TODO: Make asych*/
xiaxia686 0:1e4910aeb884 59 void RF12B::write(unsigned char *data, unsigned char length) {
xiaxia686 0:1e4910aeb884 60 unsigned char crc = 0;
xiaxia686 0:1e4910aeb884 61
xiaxia686 0:1e4910aeb884 62 /* Transmitter mode */
xiaxia686 0:1e4910aeb884 63 changeMode(TX);
xiaxia686 0:1e4910aeb884 64
xiaxia686 0:1e4910aeb884 65 writeCmd(0x0000);
xiaxia686 0:1e4910aeb884 66 send(0xAA); // PREAMBLE
xiaxia686 0:1e4910aeb884 67 send(0xAA);
xiaxia686 0:1e4910aeb884 68 send(0xAA);
xiaxia686 0:1e4910aeb884 69 send(0x2D); // SYNC
xiaxia686 0:1e4910aeb884 70 send(0xD4);
xiaxia686 0:1e4910aeb884 71 /* Packet Length */
xiaxia686 0:1e4910aeb884 72 send(length);
xiaxia686 0:1e4910aeb884 73 crc = crc8(crc, length);
xiaxia686 0:1e4910aeb884 74 send(crc);
xiaxia686 0:1e4910aeb884 75 crc = crc8(crc, crc);
xiaxia686 0:1e4910aeb884 76 /* Packet Data */
xiaxia686 0:1e4910aeb884 77 for (unsigned char i=0; i<length; i++) {
xiaxia686 0:1e4910aeb884 78 send(data[i]);
xiaxia686 0:1e4910aeb884 79 crc = crc8(crc, data[i]);
xiaxia686 0:1e4910aeb884 80 }
xiaxia686 0:1e4910aeb884 81 send(crc);
xiaxia686 0:1e4910aeb884 82 send(0xAA); // DUMMY BYTES
xiaxia686 0:1e4910aeb884 83 send(0xAA);
xiaxia686 0:1e4910aeb884 84 send(0xAA);
xiaxia686 0:1e4910aeb884 85
xiaxia686 0:1e4910aeb884 86 /* Back to receiver mode */
xiaxia686 0:1e4910aeb884 87 changeMode(RX);
xiaxia686 0:1e4910aeb884 88 status();
xiaxia686 0:1e4910aeb884 89
xiaxia686 0:1e4910aeb884 90
xiaxia686 0:1e4910aeb884 91 }
xiaxia686 0:1e4910aeb884 92
xiaxia686 0:1e4910aeb884 93 /* Transmit a 1-byte data packet */
xiaxia686 0:1e4910aeb884 94 void RF12B::write(unsigned char data) {
xiaxia686 0:1e4910aeb884 95 write(&data, 1);
xiaxia686 0:1e4910aeb884 96 }
xiaxia686 0:1e4910aeb884 97
xiaxia686 0:1e4910aeb884 98 void RF12B::write(queue<char> &data, int length) {
xiaxia686 0:1e4910aeb884 99 char crc = 0;
xiaxia686 0:1e4910aeb884 100 char length_byte = 0;
xiaxia686 0:1e4910aeb884 101
xiaxia686 0:1e4910aeb884 102 /* -1 means try to transmit everything in the queue */
xiaxia686 0:1e4910aeb884 103 if(length == -1) {
xiaxia686 0:1e4910aeb884 104 length = data.size();
xiaxia686 0:1e4910aeb884 105 }
xiaxia686 0:1e4910aeb884 106
xiaxia686 0:1e4910aeb884 107 /* max length of packet is 255 */
xiaxia686 0:1e4910aeb884 108 length_byte = min(length, 255);
xiaxia686 0:1e4910aeb884 109
xiaxia686 0:1e4910aeb884 110 /* Transmitter mode */
xiaxia686 0:1e4910aeb884 111 changeMode(TX);
xiaxia686 0:1e4910aeb884 112
xiaxia686 0:1e4910aeb884 113 writeCmd(0x0000);
xiaxia686 0:1e4910aeb884 114 send(0xAA); // PREAMBLE
xiaxia686 0:1e4910aeb884 115 send(0xAA);
xiaxia686 0:1e4910aeb884 116 send(0xAA);
xiaxia686 0:1e4910aeb884 117 send(0x2D); // SYNC
xiaxia686 0:1e4910aeb884 118 send(0xD4);
xiaxia686 0:1e4910aeb884 119 /* Packet Length */
xiaxia686 0:1e4910aeb884 120 send(length_byte);
xiaxia686 0:1e4910aeb884 121 crc = crc8(crc, length_byte);
xiaxia686 0:1e4910aeb884 122 send(crc);
xiaxia686 0:1e4910aeb884 123 crc = crc8(crc, crc);
xiaxia686 0:1e4910aeb884 124 /* Packet Data */
xiaxia686 0:1e4910aeb884 125 for (char i=0; i<length_byte; i++) {
xiaxia686 0:1e4910aeb884 126 send(data.front());
xiaxia686 0:1e4910aeb884 127 crc = crc8(crc, data.front());
xiaxia686 0:1e4910aeb884 128 data.pop();
xiaxia686 0:1e4910aeb884 129 }
xiaxia686 0:1e4910aeb884 130 send(crc);
xiaxia686 0:1e4910aeb884 131 send(0xAA); // DUMMY BYTES
xiaxia686 0:1e4910aeb884 132 send(0xAA);
xiaxia686 0:1e4910aeb884 133 send(0xAA);
xiaxia686 0:1e4910aeb884 134
xiaxia686 0:1e4910aeb884 135 /* Back to receiver mode */
xiaxia686 0:1e4910aeb884 136 changeMode(RX);
xiaxia686 0:1e4910aeb884 137 status();
xiaxia686 0:1e4910aeb884 138 }
xiaxia686 0:1e4910aeb884 139
xiaxia686 0:1e4910aeb884 140 /**********************************************************************
xiaxia686 0:1e4910aeb884 141 * PRIVATE FUNCTIONS
xiaxia686 0:1e4910aeb884 142 *********************************************************************/
xiaxia686 0:1e4910aeb884 143
xiaxia686 0:1e4910aeb884 144 /* Initialises the RF12B module */
xiaxia686 0:1e4910aeb884 145 void RF12B::init() {
xiaxia686 0:1e4910aeb884 146 /* writeCmd(0x80E7); //EL,EF,868band,12.0pF
xiaxia686 0:1e4910aeb884 147 changeMode(RX);
xiaxia686 0:1e4910aeb884 148 writeCmd(0xA640); //frequency select
xiaxia686 0:1e4910aeb884 149 writeCmd(0xC647); //4.8kbps
xiaxia686 0:1e4910aeb884 150 writeCmd(0x94A0); //VDI,FAST,134kHz,0dBm,-103dBm
xiaxia686 0:1e4910aeb884 151 writeCmd(0xC2AC); //AL,!ml,DIG,DQD4
xiaxia686 0:1e4910aeb884 152 writeCmd(0xCA81); //FIFO8,SYNC,!ff,DR
xiaxia686 0:1e4910aeb884 153 writeCmd(0xCED4); //SYNC=2DD4
xiaxia686 0:1e4910aeb884 154 writeCmd(0xC483); //@PWR,NO RSTRIC,!st,!fi,OE,EN
xiaxia686 0:1e4910aeb884 155 writeCmd(0x9850); //!mp,90kHz,MAX OUT
xiaxia686 0:1e4910aeb884 156 writeCmd(0xCC17); //OB1, COB0, LPX, Iddy, CDDIT&#65533;CBW0
xiaxia686 0:1e4910aeb884 157 writeCmd(0xE000); //NOT USED
xiaxia686 0:1e4910aeb884 158 writeCmd(0xC800); //NOT USED
xiaxia686 0:1e4910aeb884 159 writeCmd(0xC040); //1.66MHz,2.2V */
xiaxia686 0:1e4910aeb884 160
xiaxia686 0:1e4910aeb884 161 writeCmd(
xiaxia686 0:1e4910aeb884 162 RFM_CONFIG_EL |
xiaxia686 0:1e4910aeb884 163 RFM_CONFIG_EF |
xiaxia686 0:1e4910aeb884 164 RFM_CONFIG_BAND_433 //|
xiaxia686 0:1e4910aeb884 165 //RFM_CONFIG_X_11_0pf // meh, using default
xiaxia686 0:1e4910aeb884 166 );
xiaxia686 0:1e4910aeb884 167
xiaxia686 0:1e4910aeb884 168 // 2. Power Management Command
xiaxia686 0:1e4910aeb884 169 // leave everything switched off for now
xiaxia686 0:1e4910aeb884 170 /*
xiaxia686 0:1e4910aeb884 171 writeCmd(
xiaxia686 0:1e4910aeb884 172 RFM_POWER_MANAGEMENT // switch all off
xiaxia686 0:1e4910aeb884 173 );
xiaxia686 0:1e4910aeb884 174 */
xiaxia686 0:1e4910aeb884 175
xiaxia686 0:1e4910aeb884 176 // 3. Frequency Setting Command
xiaxia686 0:1e4910aeb884 177 writeCmd(
xiaxia686 0:1e4910aeb884 178 RFM_FREQUENCY |
xiaxia686 0:1e4910aeb884 179 RFM_FREQ_433Band(435.7) //I totally made this value up... if someone knows where the sweetspots are in this band, tell me!
xiaxia686 0:1e4910aeb884 180 );
xiaxia686 0:1e4910aeb884 181
xiaxia686 0:1e4910aeb884 182
xiaxia686 0:1e4910aeb884 183 // 4. Data Rate Command
xiaxia686 0:1e4910aeb884 184 writeCmd(RFM_DATA_RATE_9600);
xiaxia686 0:1e4910aeb884 185
xiaxia686 0:1e4910aeb884 186
xiaxia686 0:1e4910aeb884 187 // 5. Receiver Control Command
xiaxia686 0:1e4910aeb884 188 writeCmd(
xiaxia686 0:1e4910aeb884 189 RFM_RX_CONTROL_P20_VDI |
xiaxia686 0:1e4910aeb884 190 RFM_RX_CONTROL_VDI_FAST |
xiaxia686 0:1e4910aeb884 191 //RFM_RX_CONTROL_BW(RFM_BAUD_RATE) |
xiaxia686 0:1e4910aeb884 192 RFM_RX_CONTROL_BW_134 | // CHANGE THIS TO 67 TO IMPROVE RANGE! (though the bitrate must then be below 8kbaud, and fsk modulation changed)
xiaxia686 0:1e4910aeb884 193 RFM_RX_CONTROL_GAIN_0 |
xiaxia686 0:1e4910aeb884 194 RFM_RX_CONTROL_RSSI_103 // Might need adjustment. Datasheet says around 10^-5 bit error rate at this level and baudrate.
xiaxia686 0:1e4910aeb884 195 );
xiaxia686 0:1e4910aeb884 196
xiaxia686 0:1e4910aeb884 197 // 6. Data Filter Command
xiaxia686 0:1e4910aeb884 198 writeCmd(
xiaxia686 0:1e4910aeb884 199 RFM_DATA_FILTER_AL |
xiaxia686 0:1e4910aeb884 200 RFM_DATA_FILTER_ML |
xiaxia686 0:1e4910aeb884 201 RFM_DATA_FILTER_DIG //|
xiaxia686 0:1e4910aeb884 202 //RFM_DATA_FILTER_DQD(4)
xiaxia686 0:1e4910aeb884 203 );
xiaxia686 0:1e4910aeb884 204
xiaxia686 0:1e4910aeb884 205 // 7. FIFO and Reset Mode Command
xiaxia686 0:1e4910aeb884 206 writeCmd(
xiaxia686 0:1e4910aeb884 207 RFM_FIFO_IT(8) |
xiaxia686 0:1e4910aeb884 208 RFM_FIFO_DR |
xiaxia686 0:1e4910aeb884 209 0x8 //turn on 16bit sync word
xiaxia686 0:1e4910aeb884 210 );
xiaxia686 0:1e4910aeb884 211
xiaxia686 0:1e4910aeb884 212 // 8. FIFO Syncword
xiaxia686 0:1e4910aeb884 213 // Leave as default: 0xD4
xiaxia686 0:1e4910aeb884 214
xiaxia686 0:1e4910aeb884 215 // 9. Receiver FIFO Read
xiaxia686 0:1e4910aeb884 216 // when the interupt goes high, (and if we can assume that it was a fifo fill interrupt) we can read a byte using:
xiaxia686 0:1e4910aeb884 217 // result = RFM_READ_FIFO();
xiaxia686 0:1e4910aeb884 218
xiaxia686 0:1e4910aeb884 219 // 10. AFC Command
xiaxia686 0:1e4910aeb884 220 writeCmd(
xiaxia686 0:1e4910aeb884 221 //RFM_AFC_AUTO_VDI | //Note this might be changed to improve range. Refer to datasheet.
xiaxia686 0:1e4910aeb884 222 RFM_AFC_AUTO_INDEPENDENT |
xiaxia686 0:1e4910aeb884 223 RFM_AFC_RANGE_LIMIT_7_8 |
xiaxia686 0:1e4910aeb884 224 RFM_AFC_EN |
xiaxia686 0:1e4910aeb884 225 RFM_AFC_OE |
xiaxia686 0:1e4910aeb884 226 RFM_AFC_FI
xiaxia686 0:1e4910aeb884 227 );
xiaxia686 0:1e4910aeb884 228
xiaxia686 0:1e4910aeb884 229 // 11. TX Configuration Control Command
xiaxia686 0:1e4910aeb884 230 writeCmd(
xiaxia686 0:1e4910aeb884 231 RFM_TX_CONTROL_MOD_60 |
xiaxia686 0:1e4910aeb884 232 RFM_TX_CONTROL_POW_0
xiaxia686 0:1e4910aeb884 233 );
xiaxia686 0:1e4910aeb884 234
xiaxia686 0:1e4910aeb884 235
xiaxia686 0:1e4910aeb884 236 // 12. PLL Setting Command
xiaxia686 0:1e4910aeb884 237 writeCmd(
xiaxia686 0:1e4910aeb884 238 0xCC77 & ~0x01 // Setting the PLL bandwith, less noise, but max bitrate capped at 86.2
xiaxia686 0:1e4910aeb884 239 // I think this will slow down the pll's reaction time. Not sure, check with someone!
xiaxia686 0:1e4910aeb884 240 );
xiaxia686 0:1e4910aeb884 241
xiaxia686 0:1e4910aeb884 242 changeMode(RX);
xiaxia686 0:1e4910aeb884 243 resetRX();
xiaxia686 0:1e4910aeb884 244 status();
xiaxia686 0:1e4910aeb884 245 }
xiaxia686 0:1e4910aeb884 246
xiaxia686 0:1e4910aeb884 247 /* Write a command to the RF Module */
xiaxia686 0:1e4910aeb884 248 unsigned int RF12B::writeCmd(unsigned int cmd) {
xiaxia686 0:1e4910aeb884 249 NCS = 0;
xiaxia686 0:1e4910aeb884 250 unsigned int recv = spi.write(cmd);
xiaxia686 0:1e4910aeb884 251 NCS = 1;
xiaxia686 0:1e4910aeb884 252 return recv;
xiaxia686 0:1e4910aeb884 253 }
xiaxia686 0:1e4910aeb884 254
xiaxia686 0:1e4910aeb884 255 /* Sends a byte of data across RF */
xiaxia686 0:1e4910aeb884 256 void RF12B::send(unsigned char data) {
xiaxia686 0:1e4910aeb884 257 while (NIRQ);
xiaxia686 0:1e4910aeb884 258 writeCmd(0xB800 + data);
xiaxia686 0:1e4910aeb884 259 }
xiaxia686 0:1e4910aeb884 260
xiaxia686 0:1e4910aeb884 261 /* Change the mode of the RF module to Transmitting or Receiving */
xiaxia686 0:1e4910aeb884 262 void RF12B::changeMode(rfmode_t _mode) {
xiaxia686 0:1e4910aeb884 263 mode = _mode;
xiaxia686 0:1e4910aeb884 264 if (_mode == TX) {
xiaxia686 0:1e4910aeb884 265 writeCmd(0x8239); //!er,!ebb,ET,ES,EX,!eb,!ew,DC
xiaxia686 0:1e4910aeb884 266 } else { /* mode == RX */
xiaxia686 0:1e4910aeb884 267 writeCmd(0x8299); //er,!ebb,ET,ES,EX,!eb,!ew,DC
xiaxia686 0:1e4910aeb884 268 }
xiaxia686 0:1e4910aeb884 269 }
xiaxia686 0:1e4910aeb884 270
xiaxia686 0:1e4910aeb884 271 /* Interrupt routine for data reception */
xiaxia686 0:1e4910aeb884 272 void RF12B::rxISR() {
xiaxia686 0:1e4910aeb884 273 unsigned int data = 0;
xiaxia686 0:1e4910aeb884 274 static int i = -2;
xiaxia686 0:1e4910aeb884 275 static unsigned char packet_length = 0;
xiaxia686 0:1e4910aeb884 276 static unsigned char crc = 0;
xiaxia686 0:1e4910aeb884 277 static queue<unsigned char> temp;
xiaxia686 0:1e4910aeb884 278
xiaxia686 0:1e4910aeb884 279 //Loop while interrupt is asserted
xiaxia686 0:1e4910aeb884 280 while (!NIRQ_in && mode == RX) {
xiaxia686 0:1e4910aeb884 281
xiaxia686 0:1e4910aeb884 282 /* Grab the packet's length byte */
xiaxia686 0:1e4910aeb884 283 if (i == -2) {
xiaxia686 0:1e4910aeb884 284 data = writeCmd(0x0000);
xiaxia686 0:1e4910aeb884 285 if ( (data&0x8000) ) {
xiaxia686 0:1e4910aeb884 286 data = writeCmd(0xB000);
xiaxia686 0:1e4910aeb884 287 packet_length = (data&0x00FF);
xiaxia686 0:1e4910aeb884 288 crc = crc8(crc, packet_length);
xiaxia686 0:1e4910aeb884 289 i++;
xiaxia686 0:1e4910aeb884 290 }
xiaxia686 0:1e4910aeb884 291 }
xiaxia686 0:1e4910aeb884 292
xiaxia686 0:1e4910aeb884 293 //If we exhaust the interrupt, exit
xiaxia686 0:1e4910aeb884 294 if (NIRQ_in)
xiaxia686 0:1e4910aeb884 295 break;
xiaxia686 0:1e4910aeb884 296
xiaxia686 0:1e4910aeb884 297 // Check that packet length was correct
xiaxia686 0:1e4910aeb884 298 if (i == -1) {
xiaxia686 0:1e4910aeb884 299 data = writeCmd(0x0000);
xiaxia686 0:1e4910aeb884 300 if ( (data&0x8000) ) {
xiaxia686 0:1e4910aeb884 301 data = writeCmd(0xB000);
xiaxia686 0:1e4910aeb884 302 unsigned char crcofsize = (data&0x00FF);
xiaxia686 0:1e4910aeb884 303 if (crcofsize != crc) {
xiaxia686 0:1e4910aeb884 304 //It was wrong, start over
xiaxia686 0:1e4910aeb884 305 i = -2;
xiaxia686 0:1e4910aeb884 306 packet_length = 0;
xiaxia686 0:1e4910aeb884 307 crc = 0;
xiaxia686 0:1e4910aeb884 308 temp = queue<unsigned char>();
xiaxia686 0:1e4910aeb884 309 resetRX();
xiaxia686 0:1e4910aeb884 310 } else {
xiaxia686 0:1e4910aeb884 311 crc = crc8(crc, crcofsize);
xiaxia686 0:1e4910aeb884 312 i++;
xiaxia686 0:1e4910aeb884 313 }
xiaxia686 0:1e4910aeb884 314 }
xiaxia686 0:1e4910aeb884 315 }
xiaxia686 0:1e4910aeb884 316
xiaxia686 0:1e4910aeb884 317 //If we exhaust the interrupt, exit
xiaxia686 0:1e4910aeb884 318 if (NIRQ_in)
xiaxia686 0:1e4910aeb884 319 break;
xiaxia686 0:1e4910aeb884 320
xiaxia686 0:1e4910aeb884 321 /* Grab the packet's data */
xiaxia686 0:1e4910aeb884 322 if (i >= 0 && i < packet_length) {
xiaxia686 0:1e4910aeb884 323 data = writeCmd(0x0000);
xiaxia686 0:1e4910aeb884 324 if ( (data&0x8000) ) {
xiaxia686 0:1e4910aeb884 325 data = writeCmd(0xB000);
xiaxia686 0:1e4910aeb884 326 temp.push(data&0x00FF);
xiaxia686 0:1e4910aeb884 327 crc = crc8(crc, (unsigned char)(data&0x00FF));
xiaxia686 0:1e4910aeb884 328 i++;
xiaxia686 0:1e4910aeb884 329 }
xiaxia686 0:1e4910aeb884 330 }
xiaxia686 0:1e4910aeb884 331
xiaxia686 0:1e4910aeb884 332 //If we exhaust the interrupt, exit
xiaxia686 0:1e4910aeb884 333 if (NIRQ_in)
xiaxia686 0:1e4910aeb884 334 break;
xiaxia686 0:1e4910aeb884 335
xiaxia686 0:1e4910aeb884 336 if (i >= packet_length) {
xiaxia686 0:1e4910aeb884 337 data = writeCmd(0x0000);
xiaxia686 0:1e4910aeb884 338 if ( (data&0x8000) ) {
xiaxia686 0:1e4910aeb884 339 data = writeCmd(0xB000);
xiaxia686 0:1e4910aeb884 340 if ((unsigned char)(data & 0x00FF) == crc) {
xiaxia686 0:1e4910aeb884 341 //If the checksum is correct, add our data to the end of the output buffer
xiaxia686 0:1e4910aeb884 342 while (!temp.empty()) {
xiaxia686 0:1e4910aeb884 343 fifo.push(temp.front());
xiaxia686 0:1e4910aeb884 344 temp.pop();
xiaxia686 0:1e4910aeb884 345 }
xiaxia686 0:1e4910aeb884 346 }
xiaxia686 0:1e4910aeb884 347
xiaxia686 0:1e4910aeb884 348 /* Tell RF Module we are finished, and clean up */
xiaxia686 0:1e4910aeb884 349 i = -2;
xiaxia686 0:1e4910aeb884 350 packet_length = 0;
xiaxia686 0:1e4910aeb884 351 crc = 0;
xiaxia686 0:1e4910aeb884 352 temp = queue<unsigned char>();
xiaxia686 0:1e4910aeb884 353 resetRX();
xiaxia686 0:1e4910aeb884 354 }
xiaxia686 0:1e4910aeb884 355 }
xiaxia686 0:1e4910aeb884 356 }
xiaxia686 0:1e4910aeb884 357 }
xiaxia686 0:1e4910aeb884 358
xiaxia686 0:1e4910aeb884 359 unsigned int RF12B::status() {
xiaxia686 0:1e4910aeb884 360 return writeCmd(0x0000);
xiaxia686 0:1e4910aeb884 361 }
xiaxia686 0:1e4910aeb884 362
xiaxia686 0:1e4910aeb884 363 /* Tell the RF Module this packet is received and wait for the next */
xiaxia686 0:1e4910aeb884 364 void RF12B::resetRX() {
xiaxia686 0:1e4910aeb884 365 writeCmd(0xCA81);
xiaxia686 0:1e4910aeb884 366 writeCmd(0xCA83);
xiaxia686 0:1e4910aeb884 367 };
xiaxia686 0:1e4910aeb884 368
xiaxia686 0:1e4910aeb884 369 /* Calculate CRC8 */
xiaxia686 0:1e4910aeb884 370 unsigned char RF12B::crc8(unsigned char crc, unsigned char data) {
xiaxia686 0:1e4910aeb884 371 crc = crc ^ data;
xiaxia686 0:1e4910aeb884 372 for (int i = 0; i < 8; i++) {
xiaxia686 0:1e4910aeb884 373 if (crc & 0x01) {
xiaxia686 0:1e4910aeb884 374 crc = (crc >> 1) ^ 0x8C;
xiaxia686 0:1e4910aeb884 375 } else {
xiaxia686 0:1e4910aeb884 376 crc >>= 1;
xiaxia686 0:1e4910aeb884 377 }
xiaxia686 0:1e4910aeb884 378 }
xiaxia686 0:1e4910aeb884 379 return crc;
xiaxia686 0:1e4910aeb884 380 }