gateway/main.c
2020-02-17 13:19:28 -08:00

472 lines
13 KiB
C

/*******************************************************************************
*
* Copyright (c) 2018 Dragino
*
* http://www.dragino.com
*
*******************************************************************************/
#include <string>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>
#include <sys/time.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <wiringPi.h>
#include <wiringPiSPI.h>
// #############################################
// #############################################
#define REG_FIFO 0x00
#define REG_OPMODE 0x01
#define REG_FIFO_ADDR_PTR 0x0D
#define REG_FIFO_TX_BASE_AD 0x0E
#define REG_FIFO_RX_BASE_AD 0x0F
#define REG_RX_NB_BYTES 0x13
#define REG_FIFO_RX_CURRENT_ADDR 0x10
#define REG_IRQ_FLAGS 0x12
#define REG_DIO_MAPPING_1 0x40
#define REG_DIO_MAPPING_2 0x41
#define REG_MODEM_CONFIG 0x1D
#define REG_MODEM_CONFIG2 0x1E
#define REG_MODEM_CONFIG3 0x26
#define REG_SYMB_TIMEOUT_LSB 0x1F
#define REG_PKT_SNR_VALUE 0x19
#define REG_PAYLOAD_LENGTH 0x22
#define REG_IRQ_FLAGS_MASK 0x11
#define REG_MAX_PAYLOAD_LENGTH 0x23
#define REG_HOP_PERIOD 0x24
#define REG_SYNC_WORD 0x39
#define REG_VERSION 0x42
#define PAYLOAD_LENGTH 0x40
// LOW NOISE AMPLIFIER
#define REG_LNA 0x0C
#define LNA_MAX_GAIN 0x23
#define LNA_OFF_GAIN 0x00
#define LNA_LOW_GAIN 0x20
#define RegDioMapping1 0x40 // common
#define RegDioMapping2 0x41 // common
#define RegPaConfig 0x09 // common
#define RegPaRamp 0x0A // common
#define RegPaDac 0x5A // common
#define SX72_MC2_FSK 0x00
#define SX72_MC2_SF7 0x70
#define SX72_MC2_SF8 0x80
#define SX72_MC2_SF9 0x90
#define SX72_MC2_SF10 0xA0
#define SX72_MC2_SF11 0xB0
#define SX72_MC2_SF12 0xC0
#define SX72_MC1_LOW_DATA_RATE_OPTIMIZE 0x01 // mandated for SF11 and SF12
// sx1276 RegModemConfig1
#define SX1276_MC1_BW_125 0x70
#define SX1276_MC1_BW_250 0x80
#define SX1276_MC1_BW_500 0x90
#define SX1276_MC1_CR_4_5 0x02
#define SX1276_MC1_CR_4_6 0x04
#define SX1276_MC1_CR_4_7 0x06
#define SX1276_MC1_CR_4_8 0x08
#define SX1276_MC1_IMPLICIT_HEADER_MODE_ON 0x01
// sx1276 RegModemConfig2
#define SX1276_MC2_RX_PAYLOAD_CRCON 0x04
// sx1276 RegModemConfig3
#define SX1276_MC3_LOW_DATA_RATE_OPTIMIZE 0x08
#define SX1276_MC3_AGCAUTO 0x04
// preamble for lora networks (nibbles swapped)
#define LORA_MAC_PREAMBLE 0x34
#define RXLORA_RXMODE_RSSI_REG_MODEM_CONFIG1 0x0A
#ifdef LMIC_SX1276
#define RXLORA_RXMODE_RSSI_REG_MODEM_CONFIG2 0x70
#elif LMIC_SX1272
#define RXLORA_RXMODE_RSSI_REG_MODEM_CONFIG2 0x74
#endif
// FRF
#define REG_FRF_MSB 0x06
#define REG_FRF_MID 0x07
#define REG_FRF_LSB 0x08
#define FRF_MSB 0xD9 // 868.1 Mhz
#define FRF_MID 0x06
#define FRF_LSB 0x66
// ----------------------------------------
// Constants for radio registers
#define OPMODE_LORA 0x80
#define OPMODE_MASK 0x07
#define OPMODE_SLEEP 0x00
#define OPMODE_STANDBY 0x01
#define OPMODE_FSTX 0x02
#define OPMODE_TX 0x03
#define OPMODE_FSRX 0x04
#define OPMODE_RX 0x05
#define OPMODE_RX_SINGLE 0x06
#define OPMODE_CAD 0x07
// ----------------------------------------
// Bits masking the corresponding IRQs from the radio
#define IRQ_LORA_RXTOUT_MASK 0x80
#define IRQ_LORA_RXDONE_MASK 0x40
#define IRQ_LORA_CRCERR_MASK 0x20
#define IRQ_LORA_HEADER_MASK 0x10
#define IRQ_LORA_TXDONE_MASK 0x08
#define IRQ_LORA_CDDONE_MASK 0x04
#define IRQ_LORA_FHSSCH_MASK 0x02
#define IRQ_LORA_CDDETD_MASK 0x01
// DIO function mappings D0D1D2D3
#define MAP_DIO0_LORA_RXDONE 0x00 // 00------
#define MAP_DIO0_LORA_TXDONE 0x40 // 01------
#define MAP_DIO1_LORA_RXTOUT 0x00 // --00----
#define MAP_DIO1_LORA_NOP 0x30 // --11----
#define MAP_DIO2_LORA_NOP 0xC0 // ----11--
// #############################################
// #############################################
//
typedef bool boolean;
typedef unsigned char byte;
static const int CHANNEL = 0;
char message[256];
const char tok[2] = "|";
bool sx1272 = true;
byte receivedbytes;
enum sf_t { SF7=7, SF8, SF9, SF10, SF11, SF12 };
/*******************************************************************************
*
* Configure these values!
*
*******************************************************************************/
// SX1272 - Raspberry connections
int ssPin = 6;
int dio0 = 7;
int RST = 0;
// Set spreading factor (SF7 - SF12)
sf_t sf = SF7;
// Set center frequency
uint32_t freq = 915000000; // in Mhz! (868.1)
byte hello[32] = "HELLO";
void txlora(byte *frame, byte datalen);
static void configPower (int8_t pw);
void die(const char *s)
{
perror(s);
exit(1);
}
void selectreceiver()
{
digitalWrite(ssPin, LOW);
}
void unselectreceiver()
{
digitalWrite(ssPin, HIGH);
}
byte readReg(byte addr)
{
unsigned char spibuf[2];
selectreceiver();
spibuf[0] = addr & 0x7F;
spibuf[1] = 0x00;
wiringPiSPIDataRW(CHANNEL, spibuf, 2);
unselectreceiver();
return spibuf[1];
}
void writeReg(byte addr, byte value)
{
unsigned char spibuf[2];
spibuf[0] = addr | 0x80;
spibuf[1] = value;
selectreceiver();
wiringPiSPIDataRW(CHANNEL, spibuf, 2);
unselectreceiver();
}
static void opmode (uint8_t mode) {
writeReg(REG_OPMODE, (readReg(REG_OPMODE) & ~OPMODE_MASK) | mode);
}
static void opmodeLora() {
uint8_t u = OPMODE_LORA;
if (sx1272 == false)
u |= 0x8; // TBD: sx1276 high freq
writeReg(REG_OPMODE, u);
}
void SetupLoRa()
{
digitalWrite(RST, HIGH);
delay(100);
digitalWrite(RST, LOW);
delay(100);
byte version = readReg(REG_VERSION);
if (version == 0x22) {
// sx1272
printf("SX1272 detected, starting.\n");
sx1272 = true;
} else {
// sx1276?
digitalWrite(RST, LOW);
delay(100);
digitalWrite(RST, HIGH);
delay(100);
version = readReg(REG_VERSION);
if (version == 0x12) {
// sx1276
//printf("SX1276 detected, starting.\n");
sx1272 = false;
} else {
printf("Unrecognized transceiver.\n");
//printf("Version: 0x%x\n",version);
exit(1);
}
}
opmode(OPMODE_SLEEP);
// set frequency
uint64_t frf = ((uint64_t)freq << 19) / 32000000;
writeReg(REG_FRF_MSB, (uint8_t)(frf>>16) );
writeReg(REG_FRF_MID, (uint8_t)(frf>> 8) );
writeReg(REG_FRF_LSB, (uint8_t)(frf>> 0) );
writeReg(REG_SYNC_WORD, 0x34); // LoRaWAN public sync word
if (sx1272) {
if (sf == SF11 || sf == SF12) {
writeReg(REG_MODEM_CONFIG,0x0B);
} else {
writeReg(REG_MODEM_CONFIG,0x0A);
}
writeReg(REG_MODEM_CONFIG2,(sf<<4) | 0x04);
} else {
if (sf == SF11 || sf == SF12) {
writeReg(REG_MODEM_CONFIG3,0x0C);
} else {
writeReg(REG_MODEM_CONFIG3,0x04);
}
writeReg(REG_MODEM_CONFIG,0x72);
writeReg(REG_MODEM_CONFIG2,(sf<<4) | 0x04);
}
if (sf == SF10 || sf == SF11 || sf == SF12) {
writeReg(REG_SYMB_TIMEOUT_LSB,0x05);
} else {
writeReg(REG_SYMB_TIMEOUT_LSB,0x08);
}
writeReg(REG_MAX_PAYLOAD_LENGTH,0x80);
writeReg(REG_PAYLOAD_LENGTH,PAYLOAD_LENGTH);
writeReg(REG_HOP_PERIOD,0xFF);
writeReg(REG_FIFO_ADDR_PTR, readReg(REG_FIFO_RX_BASE_AD));
writeReg(REG_LNA, LNA_MAX_GAIN);
}
boolean receive(char *payload) {
// clear rxDone
writeReg(REG_IRQ_FLAGS, 0x40);
int irqflags = readReg(REG_IRQ_FLAGS);
// payload crc: 0x20
if((irqflags & 0x20) == 0x20)
{
printf("CRC error\n");
writeReg(REG_IRQ_FLAGS, 0x20);
return false;
} else {
byte currentAddr = readReg(REG_FIFO_RX_CURRENT_ADDR);
byte receivedCount = readReg(REG_RX_NB_BYTES);
receivedbytes = receivedCount;
writeReg(REG_FIFO_ADDR_PTR, currentAddr);
for(int i = 0; i < receivedCount; i++)
{
payload[i] = (char)readReg(REG_FIFO);
}
}
return true;
}
int send(char * s) {
opmode(OPMODE_STANDBY);
txlora((byte *) s, strlen((char *) s));
SetupLoRa();
opmodeLora();
opmode(OPMODE_STANDBY);
writeReg(RegPaRamp, (readReg(RegPaRamp) & 0xF0) | 0x08);
configPower(23);
opmode(OPMODE_RX);
return 1;
}
void receivepacket() {
long int SNR;
int rssicorr;
if(digitalRead(dio0) == 1)
{
if(receive(message)) {
byte value = readReg(REG_PKT_SNR_VALUE);
if( value & 0x80 ) // The SNR sign bit is 1
{
// Invert and divide by 4
value = ( ( ~value + 1 ) & 0xFF ) >> 2;
SNR = -value;
}
else
{
// Divide by 4
SNR = ( value & 0xFF ) >> 2;
}
if (sx1272) {
rssicorr = 139;
} else {
rssicorr = 157;
}
/*
printf("Packet RSSI: %d, ", readReg(0x1A)-rssicorr);
printf("RSSI: %d, ", readReg(0x1B)-rssicorr);
printf("SNR: %li, ", SNR);
printf("Length: %i", (int)receivedbytes);
printf("\n");
printf("Payload: %s\n", message);
*/
printf("Received message: %s", message);
} // received a message
} // dio0=1
}
static void configPower (int8_t pw) {
if (sx1272 == false) {
// no boost used for now
if(pw >= 17) {
pw = 15;
} else if(pw < 2) {
pw = 2;
}
// check board type for BOOST pin
writeReg(RegPaConfig, (uint8_t)(0x80|(pw&0xf)));
writeReg(RegPaDac, readReg(RegPaDac)|0x4);
} else {
// set PA config (2-17 dBm using PA_BOOST)
if(pw > 17) {
pw = 17;
} else if(pw < 2) {
pw = 2;
}
writeReg(RegPaConfig, (uint8_t)(0x80|(pw-2)));
}
}
static void writeBuf(byte addr, byte *value, byte len) {
unsigned char spibuf[256];
spibuf[0] = addr | 0x80;
for (int i = 0; i < len; i++) {
spibuf[i + 1] = value[i];
}
selectreceiver();
wiringPiSPIDataRW(CHANNEL, spibuf, len + 1);
unselectreceiver();
}
void txlora(byte *frame, byte datalen) {
// set the IRQ mapping DIO0=TxDone DIO1=NOP DIO2=NOP
writeReg(RegDioMapping1, MAP_DIO0_LORA_TXDONE|MAP_DIO1_LORA_NOP|MAP_DIO2_LORA_NOP);
// clear all radio IRQ flags
writeReg(REG_IRQ_FLAGS, 0xFF);
// mask all IRQs but TxDone
writeReg(REG_IRQ_FLAGS_MASK, ~IRQ_LORA_TXDONE_MASK);
// initialize the payload size and address pointers
writeReg(REG_FIFO_TX_BASE_AD, 0x00);
writeReg(REG_FIFO_ADDR_PTR, 0x00);
writeReg(REG_PAYLOAD_LENGTH, datalen);
// download buffer to the radio FIFO
writeBuf(REG_FIFO, frame, datalen);
// now we actually start the transmission
opmode(OPMODE_TX);
printf("send: %s\n", frame);
}
int main (int argc, char *argv[]) {
wiringPiSetup () ;
pinMode(ssPin, OUTPUT);
pinMode(dio0, INPUT);
pinMode(RST, OUTPUT);
wiringPiSPISetup(CHANNEL, 500000);
SetupLoRa();
opmodeLora();
opmode(OPMODE_STANDBY);
writeReg(RegPaRamp, (readReg(RegPaRamp) & 0xF0) | 0x08);
configPower(23);
opmode(OPMODE_RX);
while(1) {
receivepacket();
delay(1);
}
return (0);
}