/* * A wrapper around the samd20 i2c functions. Single master only * Copyright (C) 2015 Richard Meadows * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #ifndef I2C_H #define I2C_H #include "sercom/i2c_master.h" /** * We just declare our single instance here because. Very naughty */ struct i2c_master_module i2c_master_instance; /** * I2C Write. * * address is the full write address like 0xEE */ static void i2c_master_write(uint8_t address, uint8_t* data, uint16_t data_length) { uint32_t timeout = 0; struct i2c_master_packet packet = { .address = address >> 1, .data_length = data_length, .data = data, .ten_bit_address = false, .high_speed = false, .hs_master_code = 0x0, }; while (i2c_master_write_packet_wait(&i2c_master_instance, &packet) != STATUS_OK) { /* Increment timeout counter and check if timed out. */ if (timeout++ > 1000) { break; } } } /** * I2C Read. * * address is the full write address like 0xEE */ static void i2c_master_read(uint8_t address, uint8_t* data, uint16_t data_length) { uint32_t timeout = 0; struct i2c_master_packet packet = { .address = address >> 1, .data_length = data_length, .data = data, .ten_bit_address = false, .high_speed = false, .hs_master_code = 0x0, }; while (i2c_master_read_packet_wait(&i2c_master_instance, &packet) != STATUS_OK) { /* Increment timeout counter and check if timed out. */ if (timeout++ > 1000) { break; } } } /** * I2C bus master. */ static void i2c_init(SercomI2cm* sercom, uint32_t pad0_pinmux, uint32_t pad1_pinmux) { struct i2c_master_config config_i2c_master; i2c_master_get_config_defaults(&config_i2c_master); /* Config */ config_i2c_master.buffer_timeout = 10000; config_i2c_master.baud_rate = 100; /* 100 kBaud */ /* Pinmux */ config_i2c_master.pinmux_pad0 = pad0_pinmux; config_i2c_master.pinmux_pad1 = pad1_pinmux; /* Initialize and enable device with config. */ i2c_master_init(&i2c_master_instance, sercom, &config_i2c_master); i2c_master_enable(&i2c_master_instance); } #endif /* I2C_H */