// Basic config #include "globals.h" #include "i2c.h" // Local logging tag static const char TAG[] = __FILE__; SemaphoreHandle_t I2Caccess; void i2c_init(void) { Wire.setPins(MY_DISPLAY_SDA, MY_DISPLAY_SCL); Wire.begin(); } void i2c_deinit(void) { Wire.end(); } void i2c_scan(void) { // parts of the code in this function were taken from: // // Copyright (c) 2019 BitBank Software, Inc. // Written by Larry Bank // email: bitbank@pobox.com // Project started 25/02/2019 // // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program. If not, see . BBI2C bbi2c; const char *szNames[] = { "Unknown", "SSD1306", "SH1106", "VL53L0X", "BMP180", "BMP280", "BME280", "MPU-60x0", "MPU-9250", "MCP9808", "LSM6DS3", "ADXL345", "ADS1115", "MAX44009", "MAG3110", "CCS811", "HTS221", "LPS25H", "LSM9DS1", "LM8330", "DS3231", "LIS3DH", "LIS3DSH", "INA219", "SHT3X", "HDC1080", "MPU6886", "BME680", "AXP202", "AXP192", "24AA02XEXX", "DS1307"}; ESP_LOGI(TAG, "Starting I2C bus scan..."); memset(&bbi2c, 0, sizeof(bbi2c)); bbi2c.bWire = 1; bbi2c.iSDA = MY_DISPLAY_SDA; bbi2c.iSCL = MY_DISPLAY_SCL; I2CInit(&bbi2c, 100000L); // Scan at 100KHz low speed delay(100); // allow devices to power up uint8_t map[16]; uint8_t i; int iDevice, iCount; I2CScan(&bbi2c, map); // get bitmap of connected I2C devices if (map[0] == 0xfe) // something is wrong with the I2C bus { ESP_LOGI(TAG, "I2C pins are not correct or the bus is being pulled low " "by a bad device; unable to run scan"); } else { iCount = 0; for (i = 1; i < 128; i++) // skip address 0 (general call address) since // more than 1 device can respond { if (map[i >> 3] & (1 << (i & 7))) // device found { iCount++; iDevice = I2CDiscoverDevice(&bbi2c, i); ESP_LOGI(TAG, "Device found at 0x%X, type = %s", i, szNames[iDevice]); // show the device name as a string } } // for i ESP_LOGI(TAG, "%u I2C device(s) found", iCount); } } // functions for i2c r/w access, mutexing is done by Wire.cpp int i2c_readBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len) { 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: return ret ? ret : 0xFF; } int i2c_writeBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len) { 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(); return ret ? ret : 0xFF; }