nRF24L01P_Maniacbug.cpp

00001 /*
00002  Copyright (C) 2011 J. Coliz <maniacbug@ymail.com>
00003 
00004  This program is free software; you can redistribute it and/or
00005  modify it under the terms of the GNU General Public License
00006  version 2 as published by the Free Software Foundation.
00007  */
00008 
00009 #include "nRF24L01P_Maniacbug.h"
00010 #include "rf24_config.h"
00011 /****************************************************************************/
00012 
00013 void RF24::csn(int mode)
00014 {
00015   // Minimum ideal spi bus speed is 2x data rate
00016   // If we assume 2Mbs data rate and 16Mhz clock, a
00017   // divider of 4 is the minimum we want.
00018   // CLK:BUS 8Mhz:2Mhz, 16Mhz:4Mhz, or 20Mhz:5Mhz
00019 //#ifdef ARDUINO
00020 //  spi.setBitOrder(MSBFIRST);
00021 //  spi.setDataMode(spi_MODE0);
00022 //  spi.setClockDivider(spi_CLOCK_DIV4);
00023 //#endif
00024 //  digitalWrite(csn_pin,mode);
00025     csn_pin = mode;
00026     
00027 }
00028 
00029 /****************************************************************************/
00030 
00031 void RF24::ce(int level)
00032 {
00033   //digitalWrite(ce_pin,level);
00034   ce_pin = level;
00035 }
00036 
00037 /****************************************************************************/
00038 
00039 uint8_t RF24::read_register(uint8_t reg, uint8_t* buf, uint8_t len)
00040 {
00041   uint8_t status;
00042 
00043   csn(LOW);
00044   status = spi.write( R_REGISTER | ( REGISTER_MASK & reg ) );
00045   while ( len-- )
00046     *buf++ = spi.write(0xff);
00047 
00048   csn(HIGH);
00049 
00050   return status;
00051 }
00052 
00053 /****************************************************************************/
00054 
00055 uint8_t RF24::read_register(uint8_t reg)
00056 {
00057   csn(LOW);
00058   spi.write( R_REGISTER | ( REGISTER_MASK & reg ) );
00059   uint8_t result = spi.write(0xff);
00060 
00061   csn(HIGH);
00062   return result;
00063 }
00064 
00065 /****************************************************************************/
00066 
00067 uint8_t RF24::write_register(uint8_t reg, const uint8_t* buf, uint8_t len)
00068 {
00069   uint8_t status;
00070 
00071   csn(LOW);
00072   status = spi.write( W_REGISTER | ( REGISTER_MASK & reg ) );
00073   while ( len-- )
00074     spi.write(*buf++);
00075 
00076   csn(HIGH);
00077 
00078   return status;
00079 }
00080 
00081 /****************************************************************************/
00082 
00083 uint8_t RF24::write_register(uint8_t reg, uint8_t value)
00084 {
00085   uint8_t status;
00086 
00087 //  IF_SERIAL_DEBUG(printf(("write_register(%02x,%02x)\r\n"),reg,value));
00088 
00089   csn(LOW);
00090   status = spi.write( W_REGISTER | ( REGISTER_MASK & reg ) );
00091   spi.write(value);
00092   csn(HIGH);
00093 
00094   return status;
00095 }
00096 
00097 /****************************************************************************/
00098 
00099 uint8_t RF24::write_payload(const void* buf, uint8_t len)
00100 {
00101   uint8_t status;
00102 
00103   const uint8_t* current = reinterpret_cast<const uint8_t*>(buf);
00104 
00105   uint8_t data_len = min(len,payload_size);
00106   uint8_t blank_len = dynamic_payloads_enabled ? 0 : payload_size - data_len;
00107   
00108   //printf("[Writing %u bytes %u blanks]",data_len,blank_len);
00109   
00110   csn(LOW);
00111   status = spi.write( W_TX_PAYLOAD );
00112   while ( data_len-- )
00113     spi.write(*current++);
00114   while ( blank_len-- )
00115     spi.write(0);
00116   csn(HIGH);
00117 
00118   return status;
00119 }
00120 
00121 /****************************************************************************/
00122 
00123 uint8_t RF24::read_payload(void* buf, uint8_t len)
00124 {
00125   uint8_t status;
00126   uint8_t* current = reinterpret_cast<uint8_t*>(buf);
00127 
00128   uint8_t data_len = min(len,payload_size);
00129   uint8_t blank_len = dynamic_payloads_enabled ? 0 : payload_size - data_len;
00130   
00131   //printf("[Reading %u bytes %u blanks]",data_len,blank_len);
00132   
00133   csn(LOW);
00134   status = spi.write( R_RX_PAYLOAD );
00135   while ( data_len-- )
00136     *current++ = spi.write(0xff);
00137   while ( blank_len-- )
00138     spi.write(0xff);
00139   csn(HIGH);
00140 
00141   return status;
00142 }
00143 
00144 /****************************************************************************/
00145 
00146 uint8_t RF24::flush_rx(void)
00147 {
00148   uint8_t status;
00149 
00150   csn(LOW);
00151   status = spi.write( FLUSH_RX );
00152   csn(HIGH);
00153 
00154   return status;
00155 }
00156 
00157 /****************************************************************************/
00158 
00159 uint8_t RF24::flush_tx(void)
00160 {
00161   uint8_t status;
00162 
00163   csn(LOW);
00164   status = spi.write( FLUSH_TX );
00165   csn(HIGH);
00166 
00167   return status;
00168 }
00169 
00170 /****************************************************************************/
00171 
00172 uint8_t RF24::get_status(void)
00173 {
00174   uint8_t status;
00175 
00176   csn(LOW);
00177   status = spi.write( NOP );
00178   csn(HIGH);
00179 
00180   return status;
00181 }
00182 
00183 /****************************************************************************/
00184 
00185 void RF24::print_status(uint8_t status)
00186 {
00187   printf(("STATUS\t\t = 0x%02x RX_DR=%x TX_DS=%x MAX_RT=%x RX_P_NO=%x TX_FULL=%x\r\n"),
00188            status,
00189            (status & _BV(RX_DR))?1:0,
00190            (status & _BV(TX_DS))?1:0,
00191            (status & _BV(MAX_RT))?1:0,
00192            ((status >> RX_P_NO) & 7),
00193            (status & _BV(TX_FULL))?1:0
00194           );
00195 }
00196 
00197 /****************************************************************************/
00198 
00199 void RF24::print_observe_tx(uint8_t value)
00200 {
00201   printf(("OBSERVE_TX=%02x: POLS_CNT=%x ARC_CNT=%x\r\n"),
00202            value,
00203            (value >> PLOS_CNT) & 15,
00204            (value >> ARC_CNT) & 15
00205           );
00206 }
00207 
00208 /****************************************************************************/
00209 
00210 void RF24::print_byte_register(const char* name, uint8_t reg, uint8_t qty)
00211 {
00212 //  char extra_tab = strlen(name) < 8 ? '\t' : 0;
00213   printf("%s =",name);
00214   while (qty--)
00215     printf((" 0x%02x"),read_register(reg++));
00216   printf(("\r\n"));
00217 }
00218 
00219 /****************************************************************************/
00220 
00221 void RF24::print_address_register(const char* name, uint8_t reg, uint8_t qty)
00222 {
00223 //  char extra_tab = strlen_P(name) < 8 ? '\t' : 0;
00224   printf("%s =",name);
00225 
00226   while (qty--)
00227   {
00228     uint8_t buffer[5];
00229     read_register(reg++,buffer,sizeof buffer);
00230 
00231     printf((" 0x"));
00232     uint8_t* bufptr = buffer + sizeof buffer;
00233     while( --bufptr >= buffer )
00234       printf(("%02x"),*bufptr);
00235   }
00236 
00237   printf(("\r\n"));
00238 }
00239 
00240 /****************************************************************************/
00241 
00242 RF24::RF24(PinName mosi, PinName miso, PinName sck, PinName _csnpin, PinName _cepin):
00243   ce_pin(_cepin), csn_pin(_csnpin), wide_band(true), p_variant(false), 
00244   payload_size(32), ack_payload_available(false), dynamic_payloads_enabled(false),
00245   pipe0_reading_address(0), spi(mosi, miso, sck)
00246 {
00247     spi.frequency(10000000/5);     // 2Mbit, 1/5th the maximum transfer rate for the spi bus
00248     spi.format(8,0);                                   // 8-bit, ClockPhase = 0, ClockPolarity = 0
00249 }
00250 
00251 /****************************************************************************/
00252 
00253 void RF24::setChannel(uint8_t channel)
00254 {
00255   // TODO: This method could take advantage of the 'wide_band' calculation
00256   // done in setChannel() to require certain channel spacing.
00257 
00258   const uint8_t max_channel = 127;
00259   write_register(RF_CH,min(channel,max_channel));
00260 }
00261 
00262 /****************************************************************************/
00263 
00264 void RF24::setPayloadSize(uint8_t size)
00265 {
00266   const uint8_t max_payload_size = 32;
00267   payload_size = min(size,max_payload_size);
00268 }
00269 
00270 /****************************************************************************/
00271 
00272 uint8_t RF24::getPayloadSize(void)
00273 {
00274   return payload_size;
00275 }
00276 
00277 /****************************************************************************/
00278 
00279 static const char rf24_datarate_e_str_0[]  = "1MBPS";
00280 static const char rf24_datarate_e_str_1[]  = "2MBPS";
00281 static const char rf24_datarate_e_str_2[]  = "250KBPS";
00282 static const char * const rf24_datarate_e_str_P[]  = {
00283   rf24_datarate_e_str_0,
00284   rf24_datarate_e_str_1,
00285   rf24_datarate_e_str_2,
00286 };
00287 static const char rf24_model_e_str_0[]  = "nRF24L01";
00288 static const char rf24_model_e_str_1[]  = "nRF24L01+";
00289 static const char * const rf24_model_e_str_P[]  = {
00290   rf24_model_e_str_0,
00291   rf24_model_e_str_1,
00292 };
00293 static const char rf24_crclength_e_str_0[]  = "Disabled";
00294 static const char rf24_crclength_e_str_1[]  = "8 bits";
00295 static const char rf24_crclength_e_str_2[]  = "16 bits" ;
00296 static const char * const rf24_crclength_e_str_P[]  = {
00297   rf24_crclength_e_str_0,
00298   rf24_crclength_e_str_1,
00299   rf24_crclength_e_str_2,
00300 };
00301 static const char rf24_pa_dbm_e_str_0[]  = "PA_MIN";
00302 static const char rf24_pa_dbm_e_str_1[]  = "PA_LOW";
00303 static const char rf24_pa_dbm_e_str_2[]  = "PA_MED";
00304 static const char rf24_pa_dbm_e_str_3[]  = "PA_HIGH";
00305 static const char * const rf24_pa_dbm_e_str_P[]  = { 
00306   rf24_pa_dbm_e_str_0,
00307   rf24_pa_dbm_e_str_1,
00308   rf24_pa_dbm_e_str_2,
00309   rf24_pa_dbm_e_str_3,
00310 };
00311 
00312 void RF24::printDetails(void)
00313 {
00314   print_status(get_status());
00315 
00316   print_address_register(("RX_ADDR_P0-1"),RX_ADDR_P0,2);
00317   print_byte_register(("RX_ADDR_P2-5"),RX_ADDR_P2,4);
00318   print_address_register(("TX_ADDR"),TX_ADDR);
00319 
00320   print_byte_register(("RX_PW_P0-6"),RX_PW_P0,6);
00321   print_byte_register(("EN_AA"),EN_AA);
00322   print_byte_register(("EN_RXADDR"),EN_RXADDR);
00323   print_byte_register(("RF_CH"),RF_CH);
00324   print_byte_register(("RF_SETUP"),RF_SETUP);
00325   print_byte_register(("CONFIG"),CONFIG);
00326   print_byte_register(("DYNPD/FEATURE"),DYNPD,2);
00327 
00328   printf(("Data Rate\t = %s\r\n"), rf24_datarate_e_str_P[getDataRate()]);
00329   printf(("Model\t\t = %s\r\n"), rf24_model_e_str_P[isPVariant()]);
00330   printf(("CRC Length\t = %s\r\n"),rf24_crclength_e_str_P[getCRCLength()]);
00331   printf(("PA Power\t = %s\r\n"),rf24_pa_dbm_e_str_P[getPALevel()]);
00332 }
00333 
00334 /****************************************************************************/
00335 
00336 void RF24::begin(void)
00337 {
00338   // Initialize pins
00339 //  pinMode(ce_pin,OUTPUT);
00340 //  pinMode(csn_pin,OUTPUT);
00341 
00342   // Initialize spi bus
00343   //spi.begin();
00344   mainTimer.start();
00345 
00346   ce(LOW);
00347   csn(HIGH);
00348 
00349   // Must allow the radio time to settle else configuration bits will not necessarily stick.
00350   // This is actually only required following power up but some settling time also appears to
00351   // be required after resets too. For full coverage, we'll always assume the worst.
00352   // Enabling 16b CRC is by far the most obvious case if the wrong timing is used - or skipped.
00353   // Technically we require 4.5ms + 14us as a worst case. We'll just call it 5ms for good measure.
00354   // WARNING: wait_ms is based on P-variant whereby non-P *may* require different timing.
00355   wait_ms( 5 ) ;
00356 
00357   // Set 1500uS (minimum for 32B payload in ESB@250KBPS) timeouts, to make testing a little easier
00358   // WARNING: If this is ever lowered, either 250KBS mode with AA is broken or maximum packet
00359   // sizes must never be used. See documentation for a more complete explanation.
00360   write_register(SETUP_RETR,(4 << ARD) | (15 << ARC));
00361 
00362   // Restore our default PA level
00363   setPALevel( RF24_PA_MAX ) ;
00364 
00365   // Determine if this is a p or non-p RF24 module and then
00366   // reset our data rate back to default value. This works
00367   // because a non-P variant won't allow the data rate to
00368   // be set to 250Kbps.
00369   if( setDataRate( RF24_250KBPS ) )
00370   {
00371     p_variant = true ;
00372   }
00373   
00374   // Then set the data rate to the slowest (and most reliable) speed supported by all
00375   // hardware.
00376   setDataRate( RF24_1MBPS ) ;
00377 
00378   // Initialize CRC and request 2-byte (16bit) CRC
00379   setCRCLength( RF24_CRC_16 ) ;
00380   
00381   // Disable dynamic payloads, to match dynamic_payloads_enabled setting
00382   write_register(DYNPD,0);
00383 
00384   // Reset current status
00385   // Notice reset and flush is the last thing we do
00386   write_register(STATUS,_BV(RX_DR) | _BV(TX_DS) | _BV(MAX_RT) );
00387 
00388   // Set up default configuration.  Callers can always change it later.
00389   // This channel should be universally safe and not bleed over into adjacent
00390   // spectrum.
00391   setChannel(76);
00392 
00393   // Flush buffers
00394   flush_rx();
00395   flush_tx();
00396   
00397   // set EN_RXADDRR to 0 to fix pipe 0 from receiving
00398   write_register(EN_RXADDR, 0);
00399 }
00400 
00401 /****************************************************************************/
00402 
00403 void RF24::startListening(void)
00404 {
00405   write_register(CONFIG, read_register(CONFIG) | _BV(PWR_UP) | _BV(PRIM_RX));
00406   write_register(STATUS, _BV(RX_DR) | _BV(TX_DS) | _BV(MAX_RT) );
00407 
00408   // Restore the pipe0 adddress, if exists
00409   if (pipe0_reading_address)
00410     write_register(RX_ADDR_P0, reinterpret_cast<const uint8_t*>(&pipe0_reading_address), 5);
00411 
00412   // Flush buffers
00413   flush_rx();
00414   flush_tx();
00415 
00416   // Go!
00417   ce(HIGH);
00418 
00419   // wait for the radio to come up (130us actually only needed)
00420 //  wait_msMicroseconds(130);
00421     wait_us(130);
00422 }
00423 
00424 /****************************************************************************/
00425 
00426 void RF24::stopListening(void)
00427 {
00428   ce(LOW);
00429   flush_tx();
00430   flush_rx();
00431 }
00432 
00433 /****************************************************************************/
00434 
00435 void RF24::powerDown(void)
00436 {
00437   write_register(CONFIG,read_register(CONFIG) & ~_BV(PWR_UP));
00438 }
00439 
00440 /****************************************************************************/
00441 
00442 void RF24::powerUp(void)
00443 {
00444   write_register(CONFIG,read_register(CONFIG) | _BV(PWR_UP));
00445 }
00446 
00447 /******************************************************************/
00448 
00449 bool RF24::write( const void* buf, uint8_t len )
00450 {
00451   bool result = false;
00452 
00453   // Begin the write
00454   startWrite(buf,len);
00455 
00456   // ------------
00457   // At this point we could return from a non-blocking write, and then call
00458   // the rest after an interrupt
00459 
00460   // Instead, we are going to block here until we get TX_DS (transmission completed and ack'd)
00461   // or MAX_RT (maximum retries, transmission failed).  Also, we'll timeout in case the radio
00462   // is flaky and we get neither.
00463 
00464   // IN the end, the send should be blocking.  It comes back in 60ms worst case, or much faster
00465   // if I tighted up the retry logic.  (Default settings will be 1500us.
00466   // Monitor the send
00467   uint8_t observe_tx;
00468   uint8_t status;
00469   uint32_t sent_at = mainTimer.read_ms();
00470   const uint32_t timeout = 500; //ms to wait for timeout
00471   do
00472   {
00473     status = read_register(OBSERVE_TX,&observe_tx,1);
00474 //    IF_SERIAL_DEBUG(Serial.print(observe_tx,HEX));
00475   }
00476   while( ! ( status & ( _BV(TX_DS) | _BV(MAX_RT) ) ) && ( mainTimer.read_ms() - sent_at < timeout ) );
00477 
00478   // The part above is what you could recreate with your own interrupt handler,
00479   // and then call this when you got an interrupt
00480   // ------------
00481 
00482   // Call this when you get an interrupt
00483   // The status tells us three things
00484   // * The send was successful (TX_DS)
00485   // * The send failed, too many retries (MAX_RT)
00486   // * There is an ack packet waiting (RX_DR)
00487   bool tx_ok, tx_fail;
00488   whatHappened(tx_ok,tx_fail,ack_payload_available);
00489   
00490   //printf("%u%u%u\r\n",tx_ok,tx_fail,ack_payload_available);
00491 
00492   result = tx_ok;
00493 //  IF_SERIAL_DEBUG(Serial.print(result?"...OK.":"...Failed"));
00494 
00495   // Handle the ack packet
00496   if ( ack_payload_available )
00497   {
00498     ack_payload_length = getDynamicPayloadSize();
00499 //    IF_SERIAL_DEBUG(Serial.print("[AckPacket]/"));
00500 //    IF_SERIAL_DEBUG(Serial.println(ack_payload_length,DEC));
00501   }
00502 
00503   // Yay, we are done.
00504 
00505   // Power down
00506 //  powerDown();
00507 
00508   // Flush buffers (Is this a relic of past experimentation, and not needed anymore?
00509 //  flush_tx();
00510 
00511   return result;
00512 }
00513 /****************************************************************************/
00514 
00515 void RF24::startWrite( const void* buf, uint8_t len )
00516 {
00517   // Transmitter power-up
00518   write_register(CONFIG, ( read_register(CONFIG) | _BV(PWR_UP) ) & ~_BV(PRIM_RX) );
00519 //  wait_msMicroseconds(150);
00520     wait_us(130);
00521 
00522   // Send the payload
00523   write_payload( buf, len );
00524 
00525   // Allons!
00526   ce(HIGH);
00527 //  wait_msMicroseconds(15);
00528     wait_us(15); 
00529   ce(LOW);
00530 }
00531 
00532 /****************************************************************************/
00533 
00534 uint8_t RF24::getDynamicPayloadSize(void)
00535 {
00536   uint8_t result = 0;
00537 
00538   csn(LOW);
00539   spi.write( R_RX_PL_WID );
00540   result = spi.write(0xff);
00541   csn(HIGH);
00542 
00543   return result;
00544 }
00545 
00546 /****************************************************************************/
00547 
00548 bool RF24::available(void)
00549 {
00550   return available(NULL);
00551 }
00552 
00553 /****************************************************************************/
00554 
00555 bool RF24::available(uint8_t* pipe_num)
00556 {
00557   uint8_t status = get_status();
00558 
00559   // Too noisy, enable if you really want lots o data!!
00560   //IF_SERIAL_DEBUG(print_status(status));
00561 
00562   bool result = ( status & _BV(RX_DR) );
00563 
00564   if (result)
00565   {
00566     // If the caller wants the pipe number, include that
00567     if ( pipe_num )
00568       *pipe_num = ( status >> RX_P_NO ) & 7;
00569 
00570     // Clear the status bit
00571 
00572     // ??? Should this REALLY be cleared now?  Or wait until we
00573     // actually READ the payload?
00574 
00575     write_register(STATUS,_BV(RX_DR) );
00576 
00577     // Handle ack payload receipt
00578     if ( status & _BV(TX_DS) )
00579     {
00580       write_register(STATUS,_BV(TX_DS));
00581     }
00582   }
00583 
00584   return result;
00585 }
00586 
00587 /****************************************************************************/
00588 
00589 bool RF24::read( void* buf, uint8_t len )
00590 {
00591   // Fetch the payload
00592   read_payload( buf, len );
00593 
00594   // was this the last of the data available?
00595   return read_register(FIFO_STATUS) & _BV(RX_EMPTY);
00596 }
00597 
00598 /****************************************************************************/
00599 
00600 void RF24::whatHappened(bool& tx_ok,bool& tx_fail,bool& rx_ready)
00601 {
00602   // Read the status & reset the status in one easy call
00603   // Or is that such a good idea?
00604   uint8_t status = write_register(STATUS,_BV(RX_DR) | _BV(TX_DS) | _BV(MAX_RT) );
00605 
00606   // Report to the user what happened
00607   tx_ok = status & _BV(TX_DS);
00608   tx_fail = status & _BV(MAX_RT);
00609   rx_ready = status & _BV(RX_DR);
00610 }
00611 
00612 /****************************************************************************/
00613 
00614 void RF24::openWritingPipe(uint64_t value)
00615 {
00616   // Note that AVR 8-bit uC's store this LSB first, and the NRF24L01(+)
00617   // expects it LSB first too, so we're good.
00618 
00619   write_register(RX_ADDR_P0, reinterpret_cast<uint8_t*>(&value), 5);
00620   write_register(TX_ADDR, reinterpret_cast<uint8_t*>(&value), 5);
00621 
00622   const uint8_t max_payload_size = 32;
00623   write_register(RX_PW_P0,min(payload_size,max_payload_size));
00624   
00625   flush_tx();
00626 }
00627 
00628 /****************************************************************************/
00629 
00630 static const uint8_t child_pipe[]  =
00631 {
00632   RX_ADDR_P0, RX_ADDR_P1, RX_ADDR_P2, RX_ADDR_P3, RX_ADDR_P4, RX_ADDR_P5
00633 };
00634 static const uint8_t child_payload_size[]  =
00635 {
00636   RX_PW_P0, RX_PW_P1, RX_PW_P2, RX_PW_P3, RX_PW_P4, RX_PW_P5
00637 };
00638 static const uint8_t child_pipe_enable[]  =
00639 {
00640   ERX_P0, ERX_P1, ERX_P2, ERX_P3, ERX_P4, ERX_P5
00641 };
00642 
00643 void RF24::openReadingPipe(uint8_t child, uint64_t address)
00644 {
00645   // If this is pipe 0, cache the address.  This is needed because
00646   // openWritingPipe() will overwrite the pipe 0 address, so
00647   // startListening() will have to restore it.
00648   if (child == 0)
00649     pipe0_reading_address = address;
00650 
00651   if (child <= 6)
00652   {
00653     // For pipes 2-5, only write the LSB
00654     if ( child < 2 )
00655       write_register(child_pipe[child], reinterpret_cast<const uint8_t*>(&address), 5);
00656     else
00657       write_register(child_pipe[child], reinterpret_cast<const uint8_t*>(&address), 1);
00658 
00659     write_register(child_payload_size[child],payload_size);
00660 
00661     // Note it would be more efficient to set all of the bits for all open
00662     // pipes at once.  However, I thought it would make the calling code
00663     // more simple to do it this way.
00664     write_register(EN_RXADDR,read_register(EN_RXADDR) | _BV(child_pipe_enable[child]));
00665   }
00666 }
00667 
00668 /****************************************************************************/
00669 
00670 void RF24::toggle_features(void)
00671 {
00672   csn(LOW);
00673   spi.write( ACTIVATE );
00674   spi.write( 0x73 );
00675   csn(HIGH);
00676 }
00677 
00678 /****************************************************************************/
00679 
00680 void RF24::enableDynamicPayloads(void)
00681 {
00682   // Enable dynamic payload throughout the system
00683   write_register(FEATURE,read_register(FEATURE) | _BV(EN_DPL) );
00684 
00685   // If it didn't work, the features are not enabled
00686   if ( ! read_register(FEATURE) )
00687   {
00688     // So enable them and try again
00689     toggle_features();
00690     write_register(FEATURE,read_register(FEATURE) | _BV(EN_DPL) );
00691   }
00692 
00693 //  IF_SERIAL_DEBUG(printf("FEATURE=%i\r\n",read_register(FEATURE)));
00694 
00695   // Enable dynamic payload on all pipes
00696   //
00697   // Not sure the use case of only having dynamic payload on certain
00698   // pipes, so the library does not support it.
00699   write_register(DYNPD,read_register(DYNPD) | _BV(DPL_P5) | _BV(DPL_P4) | _BV(DPL_P3) | _BV(DPL_P2) | _BV(DPL_P1) | _BV(DPL_P0));
00700 
00701   dynamic_payloads_enabled = true;
00702 }
00703 
00704 /****************************************************************************/
00705 
00706 void RF24::enableAckPayload(void)
00707 {
00708   //
00709   // enable ack payload and dynamic payload features
00710   //
00711 
00712   write_register(FEATURE,read_register(FEATURE) | _BV(EN_ACK_PAY) | _BV(EN_DPL) );
00713 
00714   // If it didn't work, the features are not enabled
00715   if ( ! read_register(FEATURE) )
00716   {
00717     // So enable them and try again
00718     toggle_features();
00719     write_register(FEATURE,read_register(FEATURE) | _BV(EN_ACK_PAY) | _BV(EN_DPL) );
00720   }
00721 
00722 //  IF_SERIAL_DEBUG(printf("FEATURE=%i\r\n",read_register(FEATURE)));
00723 
00724   //
00725   // Enable dynamic payload on pipes 0 & 1
00726   //
00727 
00728   write_register(DYNPD,read_register(DYNPD) | _BV(DPL_P1) | _BV(DPL_P0));
00729 }
00730 
00731 /****************************************************************************/
00732 
00733 void RF24::writeAckPayload(uint8_t pipe, const void* buf, uint8_t len)
00734 {
00735   const uint8_t* current = reinterpret_cast<const uint8_t*>(buf);
00736 
00737   csn(LOW);
00738   spi.write( W_ACK_PAYLOAD | ( pipe & 7 ) );
00739   const uint8_t max_payload_size = 32;
00740   uint8_t data_len = min(len,max_payload_size);
00741   while ( data_len-- )
00742     spi.write(*current++);
00743 
00744   csn(HIGH);
00745 }
00746 
00747 /****************************************************************************/
00748 
00749 bool RF24::isAckPayloadAvailable(void)
00750 {
00751   bool result = ack_payload_available;
00752   ack_payload_available = false;
00753   return result;
00754 }
00755 
00756 /****************************************************************************/
00757 
00758 bool RF24::isPVariant(void)
00759 {
00760   return p_variant ;
00761 }
00762 
00763 /****************************************************************************/
00764 
00765 void RF24::setAutoAck(bool enable)
00766 {
00767   if ( enable )
00768     write_register(EN_AA, 63);
00769   else
00770     write_register(EN_AA, 0);
00771 }
00772 
00773 /****************************************************************************/
00774 
00775 void RF24::setAutoAck( uint8_t pipe, bool enable )
00776 {
00777   if ( pipe <= 6 )
00778   {
00779     uint8_t en_aa = read_register( EN_AA ) ;
00780     if( enable )
00781     {
00782       en_aa |= _BV(pipe) ;
00783     }
00784     else
00785     {
00786       en_aa &= ~_BV(pipe) ;
00787     }
00788     write_register( EN_AA, en_aa ) ;
00789   }
00790 }
00791 
00792 /****************************************************************************/
00793 
00794 bool RF24::testCarrier(void)
00795 {
00796   return ( read_register(CD) & 1 );
00797 }
00798 
00799 /****************************************************************************/
00800 
00801 bool RF24::testRPD(void)
00802 {
00803   return ( read_register(RPD) & 1 ) ;
00804 }
00805 
00806 /****************************************************************************/
00807 
00808 void RF24::setPALevel(rf24_pa_dbm_e level)
00809 {
00810   uint8_t setup = read_register(RF_SETUP) ;
00811   setup &= ~(_BV(RF_PWR_LOW) | _BV(RF_PWR_HIGH)) ;
00812 
00813   // switch uses RAM (evil!)
00814   if ( level == RF24_PA_MAX )
00815   {
00816     setup |= (_BV(RF_PWR_LOW) | _BV(RF_PWR_HIGH)) ;
00817   }
00818   else if ( level == RF24_PA_HIGH )
00819   {
00820     setup |= _BV(RF_PWR_HIGH) ;
00821   }
00822   else if ( level == RF24_PA_LOW )
00823   {
00824     setup |= _BV(RF_PWR_LOW);
00825   }
00826   else if ( level == RF24_PA_MIN )
00827   {
00828     // nothing
00829   }
00830   else if ( level == RF24_PA_ERROR )
00831   {
00832     // On error, go to maximum PA
00833     setup |= (_BV(RF_PWR_LOW) | _BV(RF_PWR_HIGH)) ;
00834   }
00835 
00836   write_register( RF_SETUP, setup ) ;
00837 }
00838 
00839 /****************************************************************************/
00840 
00841 rf24_pa_dbm_e RF24::getPALevel(void)
00842 {
00843   rf24_pa_dbm_e result = RF24_PA_ERROR ;
00844   uint8_t power = read_register(RF_SETUP) & (_BV(RF_PWR_LOW) | _BV(RF_PWR_HIGH)) ;
00845 
00846   // switch uses RAM (evil!)
00847   if ( power == (_BV(RF_PWR_LOW) | _BV(RF_PWR_HIGH)) )
00848   {
00849     result = RF24_PA_MAX ;
00850   }
00851   else if ( power == _BV(RF_PWR_HIGH) )
00852   {
00853     result = RF24_PA_HIGH ;
00854   }
00855   else if ( power == _BV(RF_PWR_LOW) )
00856   {
00857     result = RF24_PA_LOW ;
00858   }
00859   else
00860   {
00861     result = RF24_PA_MIN ;
00862   }
00863 
00864   return result ;
00865 }
00866 
00867 /****************************************************************************/
00868 
00869 bool RF24::setDataRate(rf24_datarate_e speed)
00870 {
00871   bool result = false;
00872   uint8_t setup = read_register(RF_SETUP) ;
00873 
00874   // HIGH and LOW '00' is 1Mbs - our default
00875   wide_band = false ;
00876   setup &= ~(_BV(RF_DR_LOW) | _BV(RF_DR_HIGH)) ;
00877   if( speed == RF24_250KBPS )
00878   {
00879     // Must set the RF_DR_LOW to 1; RF_DR_HIGH (used to be RF_DR) is already 0
00880     // Making it '10'.
00881     wide_band = false ;
00882     setup |= _BV( RF_DR_LOW ) ;
00883   }
00884   else
00885   {
00886     // Set 2Mbs, RF_DR (RF_DR_HIGH) is set 1
00887     // Making it '01'
00888     if ( speed == RF24_2MBPS )
00889     {
00890       wide_band = true ;
00891       setup |= _BV(RF_DR_HIGH);
00892     }
00893     else
00894     {
00895       // 1Mbs
00896       wide_band = false ;
00897     }
00898   }
00899   write_register(RF_SETUP,setup);
00900 
00901   // Verify our result
00902   if ( read_register(RF_SETUP) == setup )
00903   {
00904     result = true;
00905   }
00906   else
00907   {
00908     wide_band = false;
00909   }
00910 
00911   return result;
00912 }
00913 
00914 /****************************************************************************/
00915 
00916 rf24_datarate_e RF24::getDataRate( void )
00917 {
00918   rf24_datarate_e result ;
00919   uint8_t dr = read_register(RF_SETUP) & (_BV(RF_DR_LOW) | _BV(RF_DR_HIGH));
00920   
00921   // switch uses RAM (evil!)
00922   // Order matters in our case below
00923   if ( dr == _BV(RF_DR_LOW) )
00924   {
00925     // '10' = 250KBPS
00926     result = RF24_250KBPS ;
00927   }
00928   else if ( dr == _BV(RF_DR_HIGH) )
00929   {
00930     // '01' = 2MBPS
00931     result = RF24_2MBPS ;
00932   }
00933   else
00934   {
00935     // '00' = 1MBPS
00936     result = RF24_1MBPS ;
00937   }
00938   return result ;
00939 }
00940 
00941 /****************************************************************************/
00942 
00943 void RF24::setCRCLength(rf24_crclength_e length)
00944 {
00945   uint8_t config = read_register(CONFIG) & ~( _BV(CRCO) | _BV(EN_CRC)) ;
00946  
00947   if ( length == RF24_CRC_DISABLED )
00948   {
00949     // Do nothing, we turned it off above. 
00950   }
00951   else if ( length == RF24_CRC_8 )
00952   {
00953     config |= _BV(EN_CRC);
00954   }
00955   else
00956   {
00957     config |= _BV(EN_CRC);
00958     config |= _BV( CRCO );
00959   }
00960   write_register( CONFIG, config ) ;
00961 }
00962 
00963 /****************************************************************************/
00964 
00965 rf24_crclength_e RF24::getCRCLength(void)
00966 {
00967   rf24_crclength_e result = RF24_CRC_DISABLED;
00968   uint8_t config = read_register(CONFIG) & ( _BV(CRCO) | _BV(EN_CRC)) ;
00969 
00970   if ( config & _BV(EN_CRC ) )
00971   {
00972     if ( config & _BV(CRCO) )
00973       result = RF24_CRC_16;
00974     else
00975       result = RF24_CRC_8;
00976   }
00977 
00978   return result;
00979 }
00980 
00981 /****************************************************************************/
00982 
00983 void RF24::disableCRC( void )
00984 {
00985   uint8_t disable = read_register(CONFIG) & ~_BV(EN_CRC) ;
00986   write_register( CONFIG, disable ) ;
00987 }
00988 
00989 /****************************************************************************/
00990 void RF24::setRetries(uint8_t delay, uint8_t count)
00991 {
00992  write_register(SETUP_RETR,(delay&0xf)<<ARD | (count&0xf)<<ARC);
00993 }
00994 
00995 uint8_t RF24::min(uint8_t a, uint8_t b)
00996 {
00997     if(a < b)
00998         return a;
00999     else
01000         return b;
01001 }