Diff: RF12B.cpp
- Revision:
- 0:66fdbf2cc578
- Child:
- 1:27a1606deace
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/RF12B.cpp Sun Jan 01 21:54:11 2012 +0000
@@ -0,0 +1,278 @@
+/* RF12B Library. Based on work done by JeeLabs.org ported to mbed by SK Pang.
+http://jeelabs.net/projects/cafe/wiki/RF12
+
+http://opensource.org/licenses/mit-license.php
+
+Jan 2012 skpang.co.uk
+
+*/
+
+#include "RF12B.h"
+
+#include "RF_defs.h"
+// RF12 command codes
+#define RF_RECEIVER_ON 0x82DD
+#define RF_XMITTER_ON 0x823D
+#define RF_IDLE_MODE 0x820D
+#define RF_SLEEP_MODE 0x8205
+#define RF_WAKEUP_MODE 0x8207
+#define RF_TXREG_WRITE 0xB800
+#define RF_RX_FIFO_READ 0xB000
+#define RF_WAKEUP_TIMER 0xE000
+
+// RF12 status bits
+#define RF_LBD_BIT 0x0400
+#define RF_RSSI_BIT 0x0100
+
+// bits in the node id configuration byte
+#define NODE_BAND 0xC0 // frequency band
+#define NODE_ACKANY 0x20 // ack on broadcast packets if set
+#define NODE_ID 0x1F // id of this node, as A..Z or 1..31
+
+// transceiver states, these determine what to do with each interrupt
+enum {
+ TXCRC1, TXCRC2, TXTAIL, TXDONE, TXIDLE,
+ TXRECV,
+ TXPRE1, TXPRE2, TXPRE3, TXSYN1, TXSYN2,
+};
+
+DigitalOut rfled(LED3);
+DigitalOut t1(p5);
+DigitalOut t2(p6);
+
+RF12B::RF12B(PinName _SDI,
+ PinName _SDO,
+ PinName _SCK,
+ PinName _NCS,
+ PinName _NIRQ):spi(_SDI, _SDO, _SCK),
+ NCS(_NCS), NIRQ(_NIRQ), NIRQ_in(_NIRQ), rfled(LED3),t1(p5),t2(p6) {
+
+ /* SPI frequency, word lenght, polarity and phase */
+ spi.format(8,0);
+ spi.frequency(2000000);
+
+ /* Set ~CS high */
+ NCS = 1;
+
+ /* Setup interrupt to happen on falling edge of NIRQ */
+ NIRQ.fall(this, &RF12B::rxISR);
+}
+
+
+/**********************************************************************
+ * PRIVATE FUNCTIONS
+ *********************************************************************/
+
+/* Initialises the RF12B module */
+void RF12B::init(uint8_t id, uint8_t band, uint8_t g) {
+
+ nodeid = id;
+ group = g;
+ rf12_grp = g;
+
+ writeCmd(0x0000); // intitial SPI transfer added to avoid power-up problem
+ writeCmd(RF_SLEEP_MODE); // DC (disable clk pin), enable lbd
+
+ // wait until RFM12B is out of power-up reset, this takes several *seconds*
+ writeCmd(RF_TXREG_WRITE); // in case we're still in OOK mode
+
+ while (NIRQ == 0) writeCmd(0x0000);
+
+ writeCmd(0x80C7 | (2 << 4)); // EL (ena TX), EF (ena RX FIFO), 12.0pF
+ writeCmd(0xA640); // 868MHz
+ writeCmd(0xC606); // approx 49.2 Kbps, i.e. 10000/29/(1+6) Kbps
+ writeCmd(0x94A2); // VDI,FAST,134kHz,0dBm,-91dBm
+ writeCmd(0xC2AC); // AL,!ml,DIG,DQD4
+
+ writeCmd(0xCA83); // FIFO8,2-SYNC,!ff,DR
+ writeCmd(0xCE00 | 1); // SYNC=2DXX；
+
+ writeCmd(0xC483); // @PWR,NO RSTRIC,!st,!fi,OE,EN
+ writeCmd(0x9850); // !mp,90kHz,MAX OUT
+ writeCmd(0xCC77); // OB1，OB0, LPX,！ddy，DDIT，BW0
+ writeCmd(0xE000); // NOT USE
+ writeCmd(0xC800); // NOT USE
+ writeCmd(0xC049); // 1.66MHz,3.1V
+
+ rxstate = TXIDLE;
+
+ rfled = 0;
+}
+
+/* Write a command to the RF Module */
+unsigned int RF12B::writeCmd(unsigned int cmd) {
+ NCS = 0;
+ unsigned int recv = spi.write(cmd >>8);
+ recv = spi.write(cmd);
+ NCS = 1;
+ return recv;
+}
+
+/* Sends a byte of data across RF */
+void RF12B::send(unsigned char data) {
+ while (NIRQ);
+ writeCmd(0xB800 + data);
+}
+
+
+/* Interrupt routine for data reception and Txing */
+void RF12B::rxISR() {
+
+ // a transfer of 2x 16 bits @ 2 MHz over SPI takes 2x 8 us inside this ISR
+ writeCmd(0x0000);
+
+ if (rxstate == TXRECV) {
+ uint8_t in = rf12_xfer(RF_RX_FIFO_READ);
+
+ if (rxfill == 0 && group != 0)
+ rf12_buf[rxfill++] = group;
+
+ rf12_buf[rxfill++] = in;
+ rf12_crc = _crc16_update(rf12_crc, in);
+
+ if (rxfill >= rf12_len + 5 || rxfill >= RF_MAX)
+ rf12_xfer(RF_IDLE_MODE);
+ } else {
+ uint8_t out;
+
+ if (rxstate < 0) {
+ uint8_t pos = 3 + rf12_len + rxstate++;
+ out = rf12_buf[pos];
+ rf12_crc = _crc16_update(rf12_crc, out);
+ } else
+ switch (rxstate++) {
+ case TXSYN1: out = 0x2D; break;
+ case TXSYN2: out = rf12_grp; rxstate = - (2 + rf12_len); break;
+ case TXCRC1: out = rf12_crc; break;
+ case TXCRC2: out = rf12_crc >> 8; break;
+ case TXDONE: rf12_xfer(RF_IDLE_MODE); // fall through
+ default: out = 0xAA;
+ }
+
+ rf12_xfer(RF_TXREG_WRITE + out);
+ }
+ }
+
+
+void RF12B::rf12_sendStart (uint8_t hdr, const void* ptr, uint8_t len)
+{
+ rf12_len = len;
+ memcpy((void*) rf12_data, ptr, len);
+
+ rf12_sendStart2(hdr);
+
+}
+void RF12B::rf12_sendStart2 (uint8_t hdr) {
+ rf12_hdr = hdr & RF12_HDR_DST ? hdr :
+ (hdr & ~RF12_HDR_MASK) + (nodeid & NODE_ID);
+
+ /* if (crypter != 0)
+ crypter(1);
+ */
+ rf12_crc = ~0;
+
+ rf12_crc = _crc16_update(rf12_crc, rf12_grp);
+ rxstate = TXPRE1;
+
+ rf12_xfer(RF_XMITTER_ON); // bytes will be fed via interrupts
+}
+
+
+ uint16_t RF12B::rf12_xfer (uint16_t cmd) {
+ NCS = 0;
+ uint16_t reply = rf12_byte(cmd >> 8) << 8;
+ reply |= rf12_byte(cmd);
+ NCS = 1;
+ return reply;
+}
+
+ void RF12B::rf12_recvStart (void) {
+ rxfill = rf12_len = 0;
+ rf12_crc = ~0;
+
+ if (group != 0)
+ rf12_crc = _crc16_update(~0, group);
+
+ rxstate = TXRECV;
+ rf12_xfer(RF_RECEIVER_ON);
+}
+uint16_t RF12B::check_crc(void)
+{
+
+ return rf12_crc;
+}
+uint8_t RF12B::length(void)
+{
+
+ return rf12_len;
+}
+ uint8_t* RF12B::get_data(void)
+{
+ return (uint8_t*)rf12_data;
+
+}
+
+
+uint8_t RF12B::rf12_recvDone (void) {
+
+ int i;
+ if (rxstate == TXRECV && (rxfill >= rf12_len + 5 || rxfill >= RF_MAX)) {
+ rxstate = TXIDLE;
+
+ if (rf12_len > RF12_MAXDATA)
+ rf12_crc = 1; // force bad crc if packet length is invalid
+ if (!(rf12_hdr & RF12_HDR_DST) || (nodeid & NODE_ID) == 31 ||
+ (rf12_hdr & RF12_HDR_MASK) == (nodeid & NODE_ID)) {
+ /*
+ for(i=0;i<rf12_len+6;i++)
+ {
+ printf("%X ",rf12_buf[i]);
+ }
+ printf(" crc:%x",rf12_crc);
+ */
+ /*
+ if (rf12_crc == 0 && crypter != 0)
+ crypter(0);
+ else
+ rf12_seq = -1;
+ */
+ return 1; // it's a broadcast packet or it's addressed to this node
+
+ }
+ }
+ if (rxstate == TXIDLE)
+ rf12_recvStart();
+ return 0;
+}
+
+uint8_t RF12B::rf12_byte(uint8_t out)
+{
+ unsigned char recv = spi.write(out);
+
+ return recv;
+}
+
+uint16_t RF12B::_crc16_update(uint16_t crc, uint8_t data) {
+ int i;
+
+ crc ^= data;
+ for (i = 0; i < 8; ++i)
+ {
+ if (crc & 1)
+ crc = (crc >> 1) ^ 0xA001;
+ else
+ crc = (crc >> 1);
+ }
+
+ return crc;
+}
+
+
+
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+
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+
+
Sukkin Pang