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                void I2CMasterDevice::scan_i2c_bus(std::vector<uint8_t>& found_devices)
                {

                    // Write the address of each possible device and see if an ACK is received or not.
                    // TODO: Ignore reserved addresses
                    for (uint8_t address = 1; address <= 127; ++address)
                    {
                        I2CCommandLink link;
                        auto read_address = (address << 1);

                        auto res = i2c_master_start(link);
                        res |= i2c_master_write_byte(link, read_address, true);
                        res |= i2c_master_stop(link);
                        res |= i2c_master_cmd_begin(port, link, pdMS_TO_TICKS(50));

                        if (res != ESP_OK)
                        {
                            // No ACK, no device on this address
                        }
                        else
                        {
                            found_devices.push_back(address);
                        }
                    }
                }

Code: Select all

                class I2CCommandLink
                {
                    public:
                        I2CCommandLink();
                        ~I2CCommandLink();

                        operator i2c_cmd_handle_t() const
                        {
                            return cmd_link;
                        }

                    private:
                        i2c_cmd_handle_t cmd_link;
                };
                
                I2CCommandLink::I2CCommandLink()
                {
                    cmd_link = i2c_cmd_link_create();
                }

                I2CCommandLink::~I2CCommandLink()
                {
                    i2c_cmd_link_delete(cmd_link);
                }