ESP32-PaxCounter/src/i2c.cpp
2019-12-21 14:27:33 +01:00

140 lines
3.1 KiB
C++

// Basic config
#include "globals.h"
#include "i2c.h"
// Local logging tag
static const char TAG[] = __FILE__;
void i2c_init(void) {
#ifdef HAS_DISPLAY
Wire.begin(MY_OLED_SDA, MY_OLED_SCL, 400000);
#else
Wire.begin(SDA, SCL, 400000);
#endif
}
void i2c_deinit(void) {
Wire.~TwoWire(); // shutdown/power off I2C hardware
#ifdef HAS_DISPLAY
// to save power, because Wire.end() enables pullups
pinMode(MY_OLED_SDA, INPUT);
pinMode(MY_OLED_SCL, INPUT);
#else
pinMode(SDA, INPUT);
pinMode(SCL, INPUT);
#endif
}
int i2c_scan(void) {
int i2c_ret, addr;
int devices = 0;
ESP_LOGI(TAG, "Starting I2C bus scan...");
// block i2c bus access
if (I2C_MUTEX_LOCK()) {
// Scan at 100KHz low speed
Wire.setClock(100000);
for (addr = 8; addr <= 119; addr++) {
Wire.beginTransmission(addr);
Wire.write(addr);
i2c_ret = Wire.endTransmission();
if (i2c_ret == 0) {
devices++;
switch (addr) {
case SSD1306_PRIMARY_ADDRESS:
case SSD1306_SECONDARY_ADDRESS:
ESP_LOGI(TAG, "0x%X: SSD1306 Display controller", addr);
break;
case BME_PRIMARY_ADDRESS:
case BME_SECONDARY_ADDRESS:
ESP_LOGI(TAG, "0x%X: Bosch BME MEMS", addr);
break;
case AXP192_PRIMARY_ADDRESS:
ESP_LOGI(TAG, "0x%X: AXP192 power management", addr);
break;
case QUECTEL_GPS_PRIMARY_ADDRESS:
ESP_LOGI(TAG, "0x%X: Quectel GPS", addr);
break;
case MCP_24AA02E64_PRIMARY_ADDRESS:
ESP_LOGI(TAG, "0x%X: 24AA02E64 serial EEPROM", addr);
break;
default:
ESP_LOGI(TAG, "0x%X: Unknown device", addr);
break;
}
} // switch
} // for loop
ESP_LOGI(TAG, "I2C scan done, %u devices found.", devices);
// Set back to 400KHz
Wire.setClock(400000);
I2C_MUTEX_UNLOCK(); // release i2c bus access
} else
ESP_LOGE(TAG, "I2c bus busy - scan error");
return devices;
}
// mutexed functions for i2c r/w access
uint8_t i2c_readBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len) {
if (I2C_MUTEX_LOCK()) {
uint8_t ret = 0;
Wire.beginTransmission(addr);
Wire.write(reg);
Wire.endTransmission(false);
uint8_t cnt = Wire.requestFrom(addr, (uint8_t)len, (uint8_t)1);
if (!cnt)
ret = 0xFF;
uint16_t index = 0;
while (Wire.available()) {
if (index > len) {
ret = 0xFF;
goto finish;
}
data[index++] = Wire.read();
}
finish:
I2C_MUTEX_UNLOCK(); // release i2c bus access
return ret;
} else {
ESP_LOGW(TAG, "[%0.3f] i2c mutex lock failed", millis() / 1000.0);
return 0xFF;
}
}
uint8_t i2c_writeBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len) {
if (I2C_MUTEX_LOCK()) {
uint8_t ret = 0;
Wire.beginTransmission(addr);
Wire.write(reg);
for (uint16_t i = 0; i < len; i++) {
Wire.write(data[i]);
}
ret = Wire.endTransmission();
I2C_MUTEX_UNLOCK(); // release i2c bus access
return ret ? ret : 0xFF;
} else {
ESP_LOGW(TAG, "[%0.3f] i2c mutex lock failed", millis() / 1000.0);
return 0xFF;
}
}