Diff: sx127x_lora.cpp

Revision:

2:fdae76e1215e

Child:

3:3bf2515b1eed

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sx127x_lora.cpp	Wed Apr 30 22:49:43 2014 +0000
@@ -0,0 +1,424 @@
+#include "sx127x_lora.h"
+
+/* SX127x driver
+ * Copyright (c) 2013 Semtech
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//SX127x_lora::SX127x_lora(PinName mosi, PinName miso, PinName sclk, PinName cs, PinName rst, PinName dio_0, PinName dio_1, PinName fem_ctx, PinName fem_cps) : SX127x(mosi, miso, sclk, cs, rst, dio_0, dio_1, fem_ctx, fem_cps)
+SX127x_lora::SX127x_lora(SX127x r) : m_xcvr(r)
+{
+    RegModemConfig.octet = m_xcvr.read_reg(REG_LR_MODEMCONFIG);
+    RegModemConfig2.octet = m_xcvr.read_reg(REG_LR_MODEMCONFIG2);
+    RegTest31.octet = m_xcvr.read_reg(REG_LR_TEST31);
+    
+    // CRC for TX is disabled by default
+    setRxPayloadCrcOn(true);
+}
+
+SX127x_lora::~SX127x_lora()
+{
+}
+    
+void SX127x_lora::write_fifo(uint8_t len)
+{
+    int i;
+    
+    m_xcvr.m_cs = 0;
+    m_xcvr.m_spi.write(REG_FIFO | 0x80); // bit7 is high for writing to radio
+    
+    for (i = 0; i < len; i++) {
+        m_xcvr.m_spi.write(m_xcvr.tx_buf[i]);
+    }
+    m_xcvr.m_cs = 1;
+}
+
+void SX127x_lora::read_fifo(uint8_t len)
+{
+    int i;
+     
+    m_xcvr.m_cs = 0;
+    m_xcvr.m_spi.write(REG_FIFO); // bit7 is low for reading from radio
+    for (i = 0; i < len; i++) {
+        m_xcvr.rx_buf[i] = m_xcvr.m_spi.write(0);
+    }
+    m_xcvr.m_cs = 1;
+}
+
+void SX127x_lora::enable()
+{
+    m_xcvr.set_opmode(RF_OPMODE_SLEEP);
+    
+    m_xcvr.RegOpMode.bits.LongRangeMode = 1;
+    m_xcvr.write_reg(REG_OPMODE, m_xcvr.RegOpMode.octet);
+    
+    /*RegOpMode.octet = read_reg(REG_OPMODE);
+    printf("setloraon:%02x\r\n", RegOpMode.octet);*/
+    
+
+    /*                                // RxDone               RxTimeout                   FhssChangeChannel           CadDone
+    SX1272LR->RegDioMapping1 = RFLR_DIOMAPPING1_DIO0_00 | RFLR_DIOMAPPING1_DIO1_00 | RFLR_DIOMAPPING1_DIO2_00 | RFLR_DIOMAPPING1_DIO3_00;
+                                    // CadDetected          ModeReady
+    SX1272LR->RegDioMapping2 = RFLR_DIOMAPPING2_DIO4_00 | RFLR_DIOMAPPING2_DIO5_00;
+    SX1272WriteBuffer( REG_LR_DIOMAPPING1, &SX1272LR->RegDioMapping1, 2 );*/
+    m_xcvr.RegDioMapping1.bits.Dio0Mapping = 0;    // DIO0 to RxDone
+    m_xcvr.RegDioMapping1.bits.Dio1Mapping = 0;
+    m_xcvr.write_reg(REG_DIOMAPPING1, m_xcvr.RegDioMapping1.octet);
+    
+    // todo: read LoRa regsiters
+    //SX1272ReadBuffer( REG_LR_OPMODE, SX1272Regs + 1, 0x70 - 1 );
+        
+    m_xcvr.set_opmode(RF_OPMODE_STANDBY);            
+}
+
+uint8_t SX127x_lora::getCodingRate(bool from_rx)
+{
+    if (from_rx) {
+        // expected RegModemStatus was read on RxDone interrupt
+        return RegModemStatus.bits.RxCodingRate;    
+    } else {    // transmitted coding rate...
+        if (m_xcvr.type == SX1276)
+            return RegModemConfig.sx1276bits.CodingRate;
+        else if (m_xcvr.type == SX1272)
+            return RegModemConfig.sx1272bits.CodingRate;
+        else
+            return 0;
+    }
+}
+
+
+
+void SX127x_lora::setCodingRate(uint8_t cr)
+{
+    if (!m_xcvr.RegOpMode.bits.LongRangeMode)
+        return;
+        
+    if (m_xcvr.type == SX1276)
+        RegModemConfig.sx1276bits.CodingRate = cr;
+    else if (m_xcvr.type == SX1272)
+        RegModemConfig.sx1272bits.CodingRate = cr;
+    else
+        return;
+        
+    m_xcvr.write_reg(REG_LR_MODEMCONFIG, RegModemConfig.octet);
+}
+
+
+
+bool SX127x_lora::getHeaderMode(void)
+{
+    if (m_xcvr.type == SX1276)
+        return RegModemConfig.sx1276bits.ImplicitHeaderModeOn;
+    else if (m_xcvr.type == SX1272)
+        return RegModemConfig.sx1272bits.ImplicitHeaderModeOn;
+    else
+        return false;
+}
+
+void SX127x_lora::setHeaderMode(bool hm)
+{
+    if (m_xcvr.type == SX1276)
+        RegModemConfig.sx1276bits.ImplicitHeaderModeOn = hm;
+    else if (m_xcvr.type == SX1272)
+        RegModemConfig.sx1272bits.ImplicitHeaderModeOn = hm;
+    else
+        return;
+        
+    m_xcvr.write_reg(REG_LR_MODEMCONFIG, RegModemConfig.octet);
+}
+
+
+uint8_t SX127x_lora::getBw(void)
+{
+    if (m_xcvr.type == SX1276)
+        return RegModemConfig.sx1276bits.Bw;
+    else if (m_xcvr.type == SX1272)
+        return RegModemConfig.sx1272bits.Bw;
+    else
+        return 0;
+}
+
+void SX127x_lora::setBw(uint8_t bw)
+{
+    if (!m_xcvr.RegOpMode.bits.LongRangeMode)
+        return;
+        
+    if (m_xcvr.type == SX1276)
+        RegModemConfig.sx1276bits.Bw = bw;
+    else if (m_xcvr.type == SX1272) {
+        RegModemConfig.sx1272bits.Bw = bw;
+        if (RegModemConfig2.sx1272bits.SpreadingFactor > 10)
+            RegModemConfig.sx1272bits.LowDataRateOptimize = 1;
+        else
+            RegModemConfig.sx1272bits.LowDataRateOptimize = 0;
+    } else
+        return;
+        
+    m_xcvr.write_reg(REG_LR_MODEMCONFIG, RegModemConfig.octet);
+}
+
+
+
+uint8_t SX127x_lora::getSf(void)
+{
+    // spreading factor same between sx127[26]
+    return RegModemConfig2.sx1276bits.SpreadingFactor;
+}
+
+void SX127x_lora::set_nb_trig_peaks(int n)
+{
+    RegTest31.bits.detect_trig_same_peaks_nb = n;
+    m_xcvr.write_reg(REG_LR_TEST31, RegTest31.octet);
+}
+
+
+void SX127x_lora::setSf(uint8_t sf)
+{
+    if (!m_xcvr.RegOpMode.bits.LongRangeMode)
+        return;
+            
+    // false detections vs missed detections tradeoff
+    switch (sf) {
+        case 6:
+            set_nb_trig_peaks(3);
+            break;
+        case 7:
+            set_nb_trig_peaks(4);
+            break;
+        default:
+            set_nb_trig_peaks(5);
+            break;
+    }
+    
+    // write register at 0x37 with value 0xc if at SF6
+    if (sf < 7)
+        m_xcvr.write_reg(REG_LR_DETECTION_THRESHOLD, 0x0c);
+    else
+        m_xcvr.write_reg(REG_LR_DETECTION_THRESHOLD, 0x0a);
+    
+    RegModemConfig2.sx1276bits.SpreadingFactor = sf; // spreading factor same between sx127[26]
+    m_xcvr.write_reg(REG_LR_MODEMCONFIG2, RegModemConfig2.octet);
+    
+    if (m_xcvr.type == SX1272) {
+        if (sf > 10 && RegModemConfig.sx1272bits.Bw == 0)   // if bw=125KHz and sf11 or sf12
+            RegModemConfig.sx1272bits.LowDataRateOptimize = 1;
+        else
+            RegModemConfig.sx1272bits.LowDataRateOptimize = 0;
+        m_xcvr.write_reg(REG_LR_MODEMCONFIG, RegModemConfig.octet);
+    } else if (m_xcvr.type == SX1276) {
+        if (sf > 10 && RegModemConfig.sx1272bits.Bw == 0)   // if bw=125KHz and sf11 or sf12
+            RegModemConfig3.sx1276bits.LowDataRateOptimize = 1;
+        else
+            RegModemConfig3.sx1276bits.LowDataRateOptimize = 0;
+        m_xcvr.write_reg(REG_LR_MODEMCONFIG3, RegModemConfig3.octet);
+    }
+}
+
+
+        
+bool SX127x_lora::getRxPayloadCrcOn(void)
+{
+    if (m_xcvr.type == SX1276)
+        return RegModemConfig2.sx1276bits.RxPayloadCrcOn;
+    else if (m_xcvr.type == SX1272)
+        return RegModemConfig.sx1272bits.RxPayloadCrcOn;
+    else
+        return 0;
+}
+
+
+void SX127x_lora::setRxPayloadCrcOn(bool on)
+{
+    if (m_xcvr.type == SX1276) {
+        RegModemConfig2.sx1276bits.RxPayloadCrcOn = on;
+        m_xcvr.write_reg(REG_LR_MODEMCONFIG2, RegModemConfig2.octet);
+    } else if (m_xcvr.type == SX1272) {
+        RegModemConfig.sx1272bits.RxPayloadCrcOn = on;
+        m_xcvr.write_reg(REG_LR_MODEMCONFIG, RegModemConfig.octet);
+    }   
+}
+
+
+
+bool SX127x_lora::getAgcAutoOn(void)
+{
+    if (m_xcvr.type == SX1276) {
+        RegModemConfig3.octet = m_xcvr.read_reg(REG_LR_MODEMCONFIG3);
+        return RegModemConfig3.sx1276bits.AgcAutoOn;
+    } else if (m_xcvr.type == SX1272) {
+        RegModemConfig2.octet = m_xcvr.read_reg(REG_LR_MODEMCONFIG2);
+        return RegModemConfig2.sx1272bits.AgcAutoOn;
+    } else
+        return 0;
+}
+
+void SX127x_lora::setAgcAutoOn(bool on)
+{
+    if (m_xcvr.type == SX1276) {
+        RegModemConfig3.sx1276bits.AgcAutoOn = on;
+        m_xcvr.write_reg(REG_LR_MODEMCONFIG3, RegModemConfig3.octet);
+    } else if (m_xcvr.type == SX1272) {
+        RegModemConfig2.sx1272bits.AgcAutoOn = on;
+        m_xcvr.write_reg(REG_LR_MODEMCONFIG2, RegModemConfig2.octet);
+    }
+    
+}
+
+
+
+void SX127x_lora::start_tx(uint8_t len)
+{
+    if (m_xcvr.type == SX1276) {
+        // PA_BOOST on LF, RFO on HF
+        if (m_xcvr.HF) {
+            if (m_xcvr.RegPaConfig.bits.PaSelect) {
+                m_xcvr.RegPaConfig.bits.PaSelect = 0;
+                m_xcvr.write_reg(REG_PACONFIG, m_xcvr.RegPaConfig.octet);
+            }                
+        } else { // LF...
+            if (!m_xcvr.RegPaConfig.bits.PaSelect) {
+                m_xcvr.RegPaConfig.bits.PaSelect = 1;
+                m_xcvr.write_reg(REG_PACONFIG, m_xcvr.RegPaConfig.octet);
+            }        
+        }
+    } else if (m_xcvr.type == SX1272) {
+        // always PA_BOOST
+        if (!m_xcvr.RegPaConfig.bits.PaSelect) {
+            m_xcvr.RegPaConfig.bits.PaSelect = 1;
+            m_xcvr.write_reg(REG_PACONFIG, m_xcvr.RegPaConfig.octet);
+        }
+    }
+                    
+                    
+    // DIO0 to TxDone
+    if (m_xcvr.RegDioMapping1.bits.Dio0Mapping != 1) {
+        m_xcvr.RegDioMapping1.bits.Dio0Mapping = 1;
+        m_xcvr.write_reg(REG_DIOMAPPING1, m_xcvr.RegDioMapping1.octet);
+    }
+    
+    // set FifoPtrAddr to FifoTxPtrBase
+    m_xcvr.write_reg(REG_LR_FIFOADDRPTR, m_xcvr.read_reg(REG_LR_FIFOTXBASEADDR));
+    
+    // write PayloadLength bytes to fifo
+    write_fifo(len);
+
+    if (m_xcvr.HF)
+        m_xcvr.femctx = 1;
+    else
+        m_xcvr.femcps = 0;
+        
+    // radio doesnt provide FhssChangeChannel with channel=0 for TX    
+    if (RegHopPeriod > 0)
+        m_xcvr.write_reg_u24(REG_FRFMSB, m_xcvr.frfs[0]);
+        
+    m_xcvr.set_opmode(RF_OPMODE_TRANSMITTER);
+}
+
+void SX127x_lora::start_rx()
+{
+    if (!m_xcvr.RegOpMode.bits.LongRangeMode)
+        return;
+
+    if (m_xcvr.HF)
+        m_xcvr.femctx = 0;
+    else
+        m_xcvr.femcps = 1;
+        
+    if (m_xcvr.RegDioMapping1.bits.Dio0Mapping != 0) {
+        m_xcvr.RegDioMapping1.bits.Dio0Mapping = 0;    // DIO0 to RxDone
+        m_xcvr.write_reg(REG_DIOMAPPING1, m_xcvr.RegDioMapping1.octet);
+    }
+    
+    m_xcvr.write_reg(REG_LR_FIFOADDRPTR, m_xcvr.read_reg(REG_LR_FIFORXBASEADDR));
+    
+    // shouldn't be necessary, radio should provide FhssChangeChannel with channel=0 for RX  
+    if (RegHopPeriod > 0)
+        m_xcvr.write_reg_u24(REG_FRFMSB, m_xcvr.frfs[0]);
+    
+    m_xcvr.set_opmode(RF_OPMODE_RECEIVER);
+}
+
+float SX127x_lora::get_pkt_rssi()
+{
+    /* TODO: calculating with pktSNR to give meaningful result below noise floor */
+    if (m_xcvr.type == SX1276)
+        return RegPktRssiValue - 137;
+    else
+        return RegPktRssiValue - 125;
+}
+
+service_action_e SX127x_lora::service()
+{
+    if (m_xcvr.RegOpMode.bits.Mode == RF_OPMODE_RECEIVER) {
+        if (poll_vh) {
+            RegIrqFlags.octet = m_xcvr.read_reg(REG_LR_IRQFLAGS);
+            if (RegIrqFlags.bits.ValidHeader) {
+                RegIrqFlags.octet = 0;
+                RegIrqFlags.bits.ValidHeader = 1;
+                m_xcvr.write_reg(REG_LR_IRQFLAGS, RegIrqFlags.octet);
+                printf("VH\r\n");
+            }
+        }
+    }
+    
+    // FhssChangeChannel
+    if (m_xcvr.RegDioMapping1.bits.Dio1Mapping == 1) {
+        if (m_xcvr.dio1) {
+            RegHopChannel.octet = m_xcvr.read_reg(REG_LR_HOPCHANNEL);    
+            m_xcvr.write_reg_u24(REG_FRFMSB, m_xcvr.frfs[RegHopChannel.bits.FhssPresentChannel]);
+            printf("hopch:%d\r\n", RegHopChannel.bits.FhssPresentChannel);
+            RegIrqFlags.octet = 0;
+            RegIrqFlags.bits.FhssChangeChannel = 1;
+           m_xcvr. write_reg(REG_LR_IRQFLAGS, RegIrqFlags.octet);
+            
+        }
+    }
+    
+    if (m_xcvr.dio0 == 0)
+        return SERVICE_NONE;
+        
+    switch (m_xcvr.RegDioMapping1.bits.Dio0Mapping) {
+        case 0: // RxDone
+            /* user checks for CRC error in IrqFlags */
+            RegIrqFlags.octet = m_xcvr.read_reg(REG_LR_IRQFLAGS);  // save flags
+            RegHopChannel.octet = m_xcvr.read_reg(REG_LR_HOPCHANNEL);
+            if (RegIrqFlags.bits.FhssChangeChannel) {
+                m_xcvr.write_reg_u24(REG_FRFMSB, m_xcvr.frfs[RegHopChannel.bits.FhssPresentChannel]);
+            }
+            //printf("[%02x]", RegIrqFlags.octet);
+            m_xcvr.write_reg(REG_LR_IRQFLAGS, RegIrqFlags.octet); // clear flags in radio
+            
+            /* any register of interest on received packet is read(saved) here */        
+            RegModemStatus.octet = m_xcvr.read_reg(REG_LR_MODEMSTAT);          
+            RegPktSnrValue = m_xcvr.read_reg(REG_LR_PKTSNRVALUE);
+            RegPktRssiValue = m_xcvr.read_reg(REG_LR_PKTRSSIVALUE);
+            RegRxNbBytes = m_xcvr.read_reg(REG_LR_RXNBBYTES);
+    
+            m_xcvr.write_reg(REG_LR_FIFOADDRPTR, m_xcvr.read_reg(REG_LR_FIFORXCURRENTADDR));
+            read_fifo(RegRxNbBytes);
+            return SERVICE_READ_FIFO;
+        case 1: // TxDone
+            if (m_xcvr.HF)
+                m_xcvr.femctx = 0;
+            else
+                m_xcvr.femcps = 1;
+
+            RegIrqFlags.octet = 0;
+            RegIrqFlags.bits.TxDone = 1;
+            m_xcvr.write_reg(REG_LR_IRQFLAGS, RegIrqFlags.octet);                  
+            return SERVICE_TX_DONE;        
+    } // ...switch (RegDioMapping1.bits.Dio0Mapping)
+    
+    return SERVICE_ERROR;    
+}
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