pimoroni-pico/drivers/pms5003/pms5003.hpp

139 lines
4.6 KiB
C++

#include "pico/stdlib.h"
#include "hardware/uart.h"
#include "common/pimoroni_common.hpp"
#include "common/pimoroni_i2c.hpp"
#include <cstring>
constexpr char PMS5003_SOF[] = "\x42\x4d";
constexpr uint16_t PMS5003_SOFU = 0x424d;
constexpr char PMS5003_CMD_MODE_PASSIVE[] = "\xe1\x00\x00";
constexpr char PMS5003_CMD_MODE_ACTIVE[] = "\xe1\x00\x01";
constexpr char PMS5003_CMD_READ[] = "\xe2\x00\x00";
constexpr char PMS5003_CMD_SLEEP[] = "\xe4\x00\x00";
constexpr char PMS5003_CMD_WAKEUP[] = "\xe4\x00\x01";
constexpr uint PMS5003_MAX_RESET_TIME = 20000;
constexpr uint PMS5003_MAX_RESP_TIME = 5000;
constexpr uint PMS5003_MIN_CMD_INTERVAL = 100;
const uint8_t PMSA003I_DEFAULT_I2C_ADDRESS = 0x12;
class PMS5003 {
public:
#pragma pack(push, 1)
struct alignas(1) response_data {
uint16_t pm_1_0;
uint16_t pm_2_5;
uint16_t pm_10;
uint16_t pm_1_0_ao;
uint16_t pm_2_5_ao;
uint16_t pm_10_ao;
uint16_t pm_0_3_1l;
uint16_t pm_0_5_1l;
uint16_t pm_1_0_1l;
uint16_t pm_2_5_1l;
uint16_t pm_5_1l;
uint16_t pm_10_1l;
};
#pragma pack(pop)
PMS5003(uart_inst_t *uart, uint pin_tx, uint pin_rx,
uint pin_reset, uint pin_enable)
: uart(uart),
pin_tx(pin_tx),
pin_rx(pin_rx),
pin_reset(pin_reset),
pin_enable(pin_enable) {
uart_init(uart, 9600);
gpio_init(pin_tx);gpio_set_function(pin_tx, GPIO_FUNC_UART);
gpio_init(pin_rx);gpio_set_function(pin_rx, GPIO_FUNC_UART);
common_init();
};
PMS5003(pimoroni::I2C *i2c, uint pin_reset, uint pin_enable) : i2c(i2c), pin_reset(pin_reset), pin_enable(pin_enable) {
common_init();
}
~PMS5003() {};
void reset() {
sleep_ms(100);
gpio_put(pin_reset, false);
reset_input_buffer();
sleep_ms(100);
gpio_put(pin_reset, true);
if(i2c) {
sleep_ms(1000);
}
};
bool read(response_data &data) {
reset_input_buffer();
// Read the 32 byte transaction - SOF + Size + Data + CRC
if(i2c) {
i2c->read_blocking(PMSA003I_DEFAULT_I2C_ADDRESS, buffer, 32, false);
} else {
uart_read_blocking(uart, buffer, 32);
}
// test the checksum matches, if not quit early with a false return value
uint16_t checksum = (buffer[30] << 8) | buffer[31];
uint16_t compare = 0;
for(int i = 0; i < 30; i++) {
compare += buffer[i];
}
if(compare != checksum) {
return false;
}
// Copy the data into the result struct
memcpy(&data, buffer + 4, sizeof(data));
// Byteswap the results
data.pm_1_0 = __builtin_bswap16(data.pm_1_0);
data.pm_2_5 = __builtin_bswap16(data.pm_2_5);
data.pm_10 = __builtin_bswap16(data.pm_10);
data.pm_1_0_ao = __builtin_bswap16(data.pm_1_0_ao);
data.pm_2_5_ao = __builtin_bswap16(data.pm_2_5_ao);
data.pm_10_ao = __builtin_bswap16(data.pm_10_ao);
data.pm_0_3_1l = __builtin_bswap16(data.pm_0_3_1l);
data.pm_0_5_1l = __builtin_bswap16(data.pm_0_5_1l);
data.pm_1_0_1l = __builtin_bswap16(data.pm_1_0_1l);
data.pm_2_5_1l = __builtin_bswap16(data.pm_2_5_1l);
data.pm_5_1l = __builtin_bswap16(data.pm_5_1l);
data.pm_10_1l = __builtin_bswap16(data.pm_10_1l);
return true;
}
private:
// I2C mode
pimoroni::I2C *i2c = nullptr;
// UART mode
uart_inst_t *uart = nullptr;
uint pin_tx = pimoroni::PIN_UNUSED;
uint pin_rx = pimoroni::PIN_UNUSED;
uint pin_reset;
uint pin_enable;
uint8_t buffer[64];
void reset_input_buffer() {
if(i2c) return;
while(uart_is_readable(uart)) {
uart_getc(uart);
}
};
void common_init() {
gpio_init(pin_reset);gpio_set_function(pin_reset, GPIO_FUNC_SIO);gpio_set_dir(pin_reset, GPIO_OUT);gpio_put(pin_reset, false);
gpio_init(pin_enable);gpio_set_function(pin_enable, GPIO_FUNC_SIO);gpio_set_dir(pin_enable, GPIO_OUT);gpio_put(pin_enable, true);
reset();
};
};