esp32-lora/main/esp32-lora.c

594 lines
17 KiB
C

#include <string.h>
#include <math.h>
#include "freertos/FreeRTOS.h"
#include "freertos/semphr.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "esp_log.h"
#include "esp_heap_caps.h"
#include "driver/gpio.h"
#include "driver/spi_common.h"
#include "driver/spi_master.h"
#include "driver/spi_common_internal.h"
#include "esp32-lora.h"
#define READ_REG 0x7F
#define WRITE_REG 0x80
#define PA_OUTPUT_RFO_PIN 0
#define PA_OUTPUT_PA_BOOST_PIN 1
const long long frequencies[] = { 433e+6, 866e+6, 915e+6 };
const long bandwidths[] = { 7.8e3, 10.4e3, 15.6e3, 20.8e3, 31.25e3, 41.7e3, 62.5e3, 125e3, 250e3, 500e3 };
const char *TAG = "LoRa32";
static QueueHandle_t dio_event_queue;
static TaskHandle_t dio_task_handle;
static SemaphoreHandle_t spi_semaphore;
uint8_t lora32_read_reg(lora32_cfg_t *lora, uint8_t address) {
xSemaphoreTake(spi_semaphore, portMAX_DELAY);
spi_transaction_t t;
memset(&t, 0, sizeof(spi_transaction_t));
t.length = 16;
t.flags = SPI_TRANS_USE_TXDATA | SPI_TRANS_USE_RXDATA;
t.tx_data[0] = address & READ_REG;
t.tx_data[1] = 0x00;
ESP_ERROR_CHECK(spi_device_transmit(lora->spi, &t));
ESP_LOGV(TAG, "<%2X<%2X", address, t.rx_data[1]);
xSemaphoreGive(spi_semaphore);
return t.rx_data[1];
}
void lora32_write_reg(lora32_cfg_t *lora, uint8_t address, uint8_t value) {
xSemaphoreTake(spi_semaphore, portMAX_DELAY);
spi_device_handle_t spi = lora->spi;
spi_transaction_t t;
memset(&t, 0, sizeof(spi_transaction_t));
ESP_LOGV(TAG, ">%2X>%2X", address, value);
t.length = 16;
t.flags = SPI_TRANS_USE_TXDATA;
t.tx_data[0] = address | WRITE_REG;
t.tx_data[1] = value;
ESP_ERROR_CHECK(spi_device_transmit(spi, &t));
xSemaphoreGive(spi_semaphore);
};
double lora32_calc_datarate(lora32_cfg_t *lora) {
double cr = (4.0 / (long)lora->codingRate);
double sf = pow(2, lora->spreadingFactor);
double c2 = sf / bandwidths[lora->bandwidth];
ESP_LOGI(TAG, "codingRate: %d cr: %f sf: %f c2: %f", lora->codingRate, cr, sf, c2);
return lora->spreadingFactor * cr / c2 * 1000;
}
void lora23_set_explicit_header(lora32_cfg_t *lora) {
ESP_LOGD(TAG, "setting explicit header");
lora->implicitHeader = false;
lora32_write_reg(lora, REG_MODEM_CONFIG_1, lora32_read_reg(lora, REG_MODEM_CONFIG_1) & 0xFE);
}
void lora23_set_implicit_header(lora32_cfg_t *lora) {
ESP_LOGD(TAG, "setting implicit header");
lora->implicitHeader = true;
lora32_write_reg(lora, REG_MODEM_CONFIG_1, lora32_read_reg(lora, REG_MODEM_CONFIG_1) | 0x01);
}
void lora32_standby(lora32_cfg_t *lora) {
ESP_LOGV(TAG, "MODE_STANDBY");
lora32_write_reg(lora, REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_STANDBY);
}
void lora32_sleep(lora32_cfg_t *lora) {
ESP_LOGV(TAG, "MODE_SLEEP");
lora32_write_reg(lora, REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_SLEEP);
}
void lora32_enable_fhss(lora32_cfg_t *lora, uint8_t period) {
lora->enableFHSS = true;
lora32_write_reg(lora, REG_HOP_PERIOD, period);
}
void lora32_disable_fhss(lora32_cfg_t *lora) {
lora->enableFHSS = false;
lora32_write_reg(lora, REG_HOP_PERIOD, 0);
}
void lora32_enable_tx(lora32_cfg_t *lora) {
lora32_standby(lora);
if(lora->implicitHeader)
lora23_set_implicit_header(lora);
else
lora23_set_explicit_header(lora);
// zero out receive buffer
lora32_write_reg(lora, REG_FIFO_ADDR_PTR, 0);
lora32_write_reg(lora, REG_PAYLOAD_LENGTH, 0);
}
void lora32_send(lora32_cfg_t *lora, uint8_t *data, uint8_t len) {
ESP_ERROR_CHECK(spi_device_acquire_bus(lora->spi, portMAX_DELAY));
lora32_write_reg(lora, REG_DIO_MAPPING_1, DIO0_MODE_TXDONE);
lora32_enable_tx(lora);
uint8_t i = 0;
for(; (i < len && i < MAX_PKT_LENGTH); i++)
lora32_write_reg(lora, REG_FIFO, data[i]);
lora32_write_reg(lora, REG_PAYLOAD_LENGTH, len);
lora32_write_reg(lora, REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_TX);
spi_device_release_bus(lora->spi);
}
void lora32_set_frequency(lora32_cfg_t *lora, long frequency) {
ESP_LOGI(TAG, "lora32_set_frequency: %lu", frequency);
uint64_t frf = ((uint64_t)frequency << 19) / 32000000;
ESP_LOGI(TAG, "REG_FRF_MSB: 0x%2X", (uint8_t)(frf >> 16));
ESP_LOGI(TAG, "REG_FRF_MID: 0x%2X", (uint8_t)(frf >> 8));
ESP_LOGI(TAG, "REG_FRF_LSB: 0x%2X", (uint8_t)(frf >> 0));
lora32_write_reg(lora, REG_FRF_MSB, (uint8_t)(frf >> 16));
lora32_write_reg(lora, REG_FRF_MID, (uint8_t)(frf >> 8));
lora32_write_reg(lora, REG_FRF_LSB, (uint8_t)(frf >> 0));
ESP_LOGD(TAG, "REG_FRF_MSB: 0x%2X", lora32_read_reg(lora, REG_FRF_MSB));
ESP_LOGD(TAG, "REG_FRF_MID: 0x%2X", lora32_read_reg(lora, REG_FRF_MID));
ESP_LOGD(TAG, "REG_FRF_LSB: 0x%2X", lora32_read_reg(lora, REG_FRF_LSB));
}
void lora32_set_ocp(lora32_cfg_t *lora, uint8_t ma) {
}
void lora32_set_tx_power(lora32_cfg_t *lora, uint8_t level, uint8_t output) {
if(output == PA_OUTPUT_RFO_PIN) {
if(level > 14) level = 14;
lora32_write_reg(lora, REG_PA_CONFIG, 0x70 | level);
} else {
if(level > 17) {
// cap power level to 20
if(level > 20) level = 20;
level -= 3;
lora32_write_reg(lora, REG_PA_DAC, 0x07);
// TODO: set over current protection
} else {
if(level < 2) level = 2;
lora32_write_reg(lora, REG_PA_DAC, 0x04);
// TODO: set over current protection
}
lora32_write_reg(lora, REG_PA_CONFIG, PA_BOOST | (level - 2));
}
ESP_LOGI(TAG, "set_tx_power(%d, %d)", level, output);
ESP_LOGD(TAG, "REG_PA_CONFIG: 0x%2X", lora32_read_reg(lora, REG_PA_CONFIG));
}
uint8_t lora32_data_available(lora32_cfg_t *lora) {
return lora32_read_reg(lora, REG_RX_NB_BYTES) - lora->fifoIdx;
}
void lora32_dump_regs(lora32_cfg_t *lora) {
uint8_t i;
char endline[17] = {0};
printf(" ");
for(i = 0; i < 16; i++)
printf(" %X%s", i, (i % 2 == 1 ? " " : ""));
printf("\n");
for(i = 0; i < 127; i++) {
if(i % 16 == 0)
printf("0x%02X: ", i);
char c = lora32_read_reg(lora, i);
endline[i % 16] = (c >= 32 ? c : '.');
printf("%02X%s", c, i % 2 == 1 ? " " : "");
if(i % 16 == 15)
printf(" %s\n", endline);
}
printf("\n");
}
void lora32_toggle_reset(lora32_cfg_t *config) {
// toggle reset (L/H)
ESP_LOGI(TAG, "Toggling reset pin %d", config->reset);
gpio_set_level(config->reset, 0);
vTaskDelay(100 / portTICK_PERIOD_MS); // requires 100us
gpio_set_level(config->reset, 1);
vTaskDelay(100 / portTICK_PERIOD_MS); // 5ms before available
}
uint8_t lora32_get_spreadingfactor(lora32_cfg_t *lora) {
return (lora32_read_reg(lora, REG_MODEM_CONFIG_2) >> 4);
}
void lora32_set_spreadfactor(lora32_cfg_t *lora, uint8_t factor) {
if(factor <= 6) {
factor = 6;
lora32_write_reg(lora, REG_DETECTION_OPTIMIZE, DETECT_OPT_SF6);
lora32_write_reg(lora, REG_DETECTION_THRESHOLD, DETECT_THRES_SF6);
} else {
if(factor > 12) factor = 12;
lora32_write_reg(lora, REG_DETECTION_OPTIMIZE, DETECT_OPT_OTHER);
lora32_write_reg(lora, REG_DETECTION_THRESHOLD, DETECT_THRES_OTHER);
}
ESP_LOGI(TAG, "lora32_set_spreadfactor: %d", factor);
lora32_write_reg(lora, REG_MODEM_CONFIG_2, (lora32_read_reg(lora, REG_MODEM_CONFIG_2) & 0x0F) | ((factor << 4) & 0xF0));
}
void lora32_enable_single_rx(lora32_cfg_t *lora) {
ESP_LOGD(TAG, "MODE_RX_SINGLE");
if(lora->receive != NULL) {
lora32_write_reg(lora, REG_DIO_MAPPING_1, DIO0_MODE_RXDONE);
}
lora32_standby(lora);
lora32_write_reg(lora, REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_RX_SINGLE);
}
void lora32_enable_continuous_rx(lora32_cfg_t *lora) {
ESP_LOGD(TAG, "MODE_RX_CONTINUOUS");
if(lora->receive != NULL) {
lora32_write_reg(lora, REG_DIO_MAPPING_1, DIO0_MODE_RXDONE);
}
lora32_standby(lora);
lora32_write_reg(lora, REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_RX_CONTINUOUS);
}
void lora32_enable_cad(lora32_cfg_t *lora) {
if((lora->cad_done != NULL) | (lora->cad_detected != NULL)) {
ESP_LOGD(TAG, "Setting DIO0 to CAD Detect");
lora32_write_reg(lora, REG_DIO_MAPPING_1, DIO0_MODE_CADDET);
}
ESP_LOGD(TAG, "MODE_CAD_DETECT");
lora32_write_reg(lora, REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_CAD_DETECT);
}
long lora32_get_bandwidth(lora32_cfg_t *lora) {
uint8_t bw = (lora32_read_reg(lora, REG_MODEM_CONFIG_1) >> 4);
ESP_LOGI(TAG, "lora32_get_bandwidth: %d", bw);
if(bw > 9) return -1;
ESP_LOGI(TAG, "lora32_get_bandwidth: %ld", bandwidths[bw]);
return bandwidths[bw];
}
void lora32_set_ldo_flag(lora32_cfg_t *lora) {
long symbolDuration = 1000 / (lora32_get_bandwidth(lora) / (1L << lora32_get_spreadingfactor(lora)));
ESP_LOGI(TAG, "symbolDuration: %ld", symbolDuration);
bool ldoOn = symbolDuration > 16;
ESP_LOGI(TAG, "ldoOn: %d", ldoOn);
uint8_t modem_config_3 = lora32_read_reg(lora, REG_MODEM_CONFIG_3);
ESP_LOGI(TAG, "modem_config_3: %d", modem_config_3);
modem_config_3 |= ldoOn << 3;
ESP_LOGI(TAG, "modem_config_3: %d", modem_config_3);
lora32_write_reg(lora, REG_MODEM_CONFIG_3, modem_config_3);
}
void lora32_set_bandwidth(lora32_cfg_t *lora, uint8_t bw) {
ESP_LOGI(TAG, "lora32_set_bandwidth: %d", bw);
uint8_t modem_config_1 = lora32_read_reg(lora, REG_MODEM_CONFIG_1);
lora32_write_reg(lora, REG_MODEM_CONFIG_1, (modem_config_1 & 0x0F) | (bw << 4));
lora32_set_ldo_flag(lora);
}
void lora32_set_coding_rate(lora32_cfg_t *lora, uint8_t cr) {
if(cr < 5) cr = 5;
else if(cr > 8) cr = 8;
cr = cr - 4;
ESP_LOGI(TAG, "lora32_set_coding_rate: %d", cr + 4);
lora32_write_reg(lora, REG_MODEM_CONFIG_1, (lora32_read_reg(lora, REG_MODEM_CONFIG_1) & 0xF1) | (cr << 1));
}
void lora32_set_lna(lora32_cfg_t *lora, uint8_t gain) {
// clamp gain values between 0b001 & 0b110
// NOTE: don't clamp until full REG_LNA is implmented
//if(gain == 0) gain = 1;
//else if(gain > 6) gain = 6;
uint8_t lna = lora32_read_reg(lora, REG_LNA);
lora32_write_reg(lora, REG_LNA, lna | gain);
ESP_LOGI(TAG, "set lna: 0x%2X", lna | gain);
}
static void lora32_handle_receive(lora32_cfg_t *lora) {
uint8_t len = lora32_read_reg(lora, (lora->implicitHeader ? REG_PAYLOAD_LENGTH : REG_RX_NB_BYTES));
ESP_LOGD(TAG, "lora32_handle_receive packet length: %d", len);
// TODO: set FIFO address to RX address
uint8_t fifo_addr = lora32_read_reg(lora, REG_FIFO_RX_CURRENT_ADDR);
ESP_LOGD(TAG, "lora32_handle_receive current FIFO address: %d", fifo_addr);
lora32_write_reg(lora, REG_FIFO_ADDR_PTR, fifo_addr);
lora->receive(lora, len);
}
static void IRAM_ATTR lora32_dio_task(void *arg) {
// allocate lora32_cfg_t to receive config from Queu
lora32_cfg_t *lora = malloc(sizeof(lora32_cfg_t));
ESP_LOGI(TAG, "starting DIO handler task");
while(1) {
// wait for event over Queue
if(xQueueReceive(dio_event_queue, (void*)lora, portMAX_DELAY) != pdPASS) continue;
// need a better way to log which event and from which config
//ESP_LOGI(TAG, "handling DIO0 on GPIO%d", lora->dio0);
spi_device_acquire_bus(lora->spi, portMAX_DELAY);
// read IRQ flags
uint8_t irqs = lora32_read_reg(lora, REG_IRQ_FLAGS);
ESP_LOGD(TAG, "reading irqs: %02X", irqs);
// clear IRQ flags by writing mask back
ESP_LOGD(TAG, "clearing irqs");
lora32_write_reg(lora, REG_IRQ_FLAGS, irqs);
spi_device_release_bus(lora->spi);
// TODO handle header validation
if((irqs & IRQ_RX_DONE) == IRQ_RX_DONE) {
lora32_handle_receive(lora);
}
if((irqs & IRQ_TX_DONE) == IRQ_TX_DONE) {
if(lora->tx_done != NULL) lora->tx_done(lora);
}
bool cad_detected = false;
if((irqs & IRQ_CAD_DETECTED) == IRQ_CAD_DETECTED) {
// this is for the next clause, CAD Done callback gets true/false
cad_detected = true;
// no need for arg, cad_detected callback is always presummed true
if(lora->cad_detected != NULL) lora->cad_detected(lora);
}
if((irqs & IRQ_CAD_DONE) == IRQ_CAD_DONE) {
// cad_done gets true/false from above, when activity is detected
// these *should* fire at the same time, defaults to false
if(lora->cad_done != NULL) lora->cad_done(lora, cad_detected);
}
if((irqs & IRQ_FHSS_CHANGE) == IRQ_FHSS_CHANGE) {
ESP_LOGI(TAG, "switching channel %d: %d", lora->channel, lora->channels[lora->channel]);
if(lora->channel == 0 && lora->channels[lora->channel] == 0) continue;
if(lora->channels[lora->channel] == 0) {
ESP_LOGI(TAG, "reseting to channel 0");
lora->channel = 0;
}
lora32_set_frequency(lora, lora->frequency + (lora->channels[lora->channel] * bandwidths[lora->bandwidth]));
lora->channel++;
}
}
}
void lora32_read_data(lora32_cfg_t *lora, uint8_t *data) {
uint8_t i = 0;
uint8_t len = lora32_read_reg(lora, (lora->implicitHeader ? REG_PAYLOAD_LENGTH : REG_RX_NB_BYTES));
ESP_LOGI(TAG, "Reading %d bytes", len);
for(i = 0; i < len; i++) {
data[i] = lora32_read_reg(lora, REG_FIFO);
}
}
static void IRAM_ATTR lora32_on_dio(void *arg) {
xQueueSend(dio_event_queue, arg, (TickType_t)0);
}
uint8_t lora32_spi_init(lora32_cfg_t *lora) {
ESP_LOGI(TAG, "Initializing SPI bus");
esp_err_t err = ESP_OK;
spi_bus_config_t buscfg = {
.miso_io_num = lora->cipo,
.mosi_io_num = lora->copi,
.sclk_io_num = lora->clk,
.quadwp_io_num = -1,
.quadhd_io_num = -1
};
if(spi_bus_get_attr(lora->spi_host) == NULL) {
// 2 should be SPI_DMA_CH_AUTO ??? but it doesn't seem to be defined
err = spi_bus_initialize(lora->spi_host, &buscfg, 2);
}
return err;
}
uint8_t lora32_init(lora32_cfg_t *lora) {
if(spi_semaphore == NULL) {
spi_semaphore = xSemaphoreCreateMutex();
}
gpio_config_t io_conf;
io_conf.intr_type = GPIO_PIN_INTR_DISABLE;
io_conf.mode = GPIO_MODE_OUTPUT;
io_conf.pin_bit_mask = (1ULL<<lora->reset)|(1ULL<<lora->nss);
io_conf.pull_down_en = 0;
io_conf.pull_up_en = 0;
gpio_config(&io_conf);
lora32_toggle_reset(lora);
// set NSS high
ESP_LOGI(TAG, "Bringing NSS high: %d", lora->nss);
gpio_set_level(lora->nss, 1);
vTaskDelay(10 / portTICK_PERIOD_MS);
// SPI device setup
spi_device_interface_config_t devcfg = {
.clock_speed_hz = 8E6,
.flags = 0,
.mode = 0,
.spics_io_num = lora->nss,
.queue_size = 7,
};
ESP_ERROR_CHECK(spi_bus_add_device(lora->spi_host, &devcfg, &lora->spi));
// initialize event groups
lora->handle.events = xEventGroupCreate();
uint8_t version = lora32_read_reg(lora, REG_VERSION);
ESP_LOGD(TAG, "lora32_get_id() == 0x%2X", version);
// if ID does not match, something is likely wrong on the SPI bus
if(version != 0x12) {
ESP_LOGD(TAG, "REG_VERSION returned incorrectly. Expected 0x12 got 0x%02X", version);
return ERR_LOR_VERSION_MISMATCH;
}
// TODO: confirm this is happening. Before/after power measurements?
lora32_sleep(lora);
ESP_LOGI(TAG, "lora32_sleep");
// TODO: VERIFY
lora32_set_frequency(lora, lora->frequency);
lora32_set_spreadfactor(lora, lora->spreadingFactor);
lora32_set_bandwidth(lora, lora->bandwidth);
lora32_set_coding_rate(lora, lora->codingRate);
lora32_write_reg(lora, REG_FIFO_TX_BASE_ADDR, 0x00);
lora32_write_reg(lora, REG_FIFO_RX_BASE_ADDR, 0x00);
ESP_LOGI(TAG, "clear rx/tx fifos");
lora32_set_lna(lora, 0x03);
// enable auto AGC
lora32_write_reg(lora, REG_MODEM_CONFIG_3, 0x04);
// TODO make based on config
lora32_set_tx_power(lora, 17, PA_OUTPUT_PA_BOOST_PIN);
ESP_LOGI(TAG, "lora32_set_tx_power");
lora32_standby(lora);
ESP_LOGI(TAG, "lora32_standby");
if(lora->implicitHeader)
lora23_set_implicit_header(lora);
else
lora23_set_explicit_header(lora);
// TODO setup shouldn't be based on just receive callback
if(lora->receive != NULL) {
ESP_LOGI(TAG, "Setting GPIO Interrupt");
// TODO check at least one DIOx pin is not NULL
io_conf.intr_type = GPIO_PIN_INTR_POSEDGE;
io_conf.pin_bit_mask = ((1ULL << lora->dio0) | (1ULL << lora->dio1) | (1ULL << lora->dio2));
io_conf.mode = GPIO_MODE_INPUT;
io_conf.pull_down_en = 0;
io_conf.pull_up_en = 0;
gpio_config(&io_conf);
gpio_set_intr_type(lora->dio0, GPIO_INTR_POSEDGE);
gpio_set_intr_type(lora->dio1, GPIO_INTR_POSEDGE);
gpio_set_intr_type(lora->dio2, GPIO_INTR_POSEDGE);
// the DIO interrupt handling for every device is done from one task
if(dio_task_handle == NULL) {
ESP_LOGI(TAG, "Setting callback handler and ISR service");
// enable global ISR service
gpio_install_isr_service(0);
dio_event_queue = xQueueCreate(10, sizeof(lora32_cfg_t));
// this should probably be high priority
xTaskCreate(&lora32_dio_task, "lora32_dio_task", 4096, NULL, 6, &dio_task_handle);
}
// add ISR handler to the global service started (once) above
ESP_LOGI(TAG, "Installing ISR handler for GPIO%d", lora->dio0);
if(lora->dio0 > -1)
gpio_isr_handler_add(lora->dio0, lora32_on_dio, (void*)lora);
if(lora->dio1 > -1)
gpio_isr_handler_add(lora->dio1, lora32_on_dio, (void*)lora);
if(lora->dio2 > -1)
gpio_isr_handler_add(lora->dio2, lora32_on_dio, (void*)lora);
}
return 1;
};