1 /* Copyright 2018 Jack Humbert
2 * Copyright 2018 Yiancar
4 * This program is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 /* This library is only valid for STM32 processors.
19 * This library follows the convention of the AVR i2c_master library.
20 * As a result addresses are expected to be already shifted (addr << 1).
21 * I2CD1 is the default driver which corresponds to pins B6 and B7. This
23 * Please ensure that HAL_USE_I2C is TRUE in the halconf.h file and that
24 * STM32_I2C_USE_I2C1 is TRUE in the mcuconf.h file. Pins B6 and B7 are used
25 * but using any other I2C pins should be trivial.
28 #include "i2c_master.h"
32 static uint8_t i2c_address;
34 // This configures the I2C clock to 400Mhz assuming a 72Mhz clock
35 // For more info : https://www.st.com/en/embedded-software/stsw-stm32126.html
36 static const I2CConfig i2cconfig = {
37 STM32_TIMINGR_PRESC(15U) |
38 STM32_TIMINGR_SCLDEL(4U) | STM32_TIMINGR_SDADEL(2U) |
39 STM32_TIMINGR_SCLH(15U) | STM32_TIMINGR_SCLL(21U),
46 palSetGroupMode(GPIOB, GPIOB_PIN6 | GPIOB_PIN7, 0, PAL_MODE_INPUT); // Try releasing special pins for a short time
47 chThdSleepMilliseconds(10);
49 palSetPadMode(GPIOB, 6, PAL_MODE_ALTERNATE(4) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_PUPDR_PULLUP);
50 palSetPadMode(GPIOB, 7, PAL_MODE_ALTERNATE(4) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_PUPDR_PULLUP);
52 //i2cInit(); //This is invoked by halInit() so no need to redo it.
55 // This is usually not needed
56 uint8_t i2c_start(uint8_t address)
58 i2c_address = address;
59 i2cStart(&I2C_DRIVER, &i2cconfig);
63 uint8_t i2c_transmit(uint8_t address, uint8_t* data, uint16_t length, uint16_t timeout)
65 i2c_address = address;
66 i2cStart(&I2C_DRIVER, &i2cconfig);
67 return i2cMasterTransmitTimeout(&I2C_DRIVER, (i2c_address >> 1), data, length, 0, 0, MS2ST(timeout));
70 uint8_t i2c_receive(uint8_t address, uint8_t* data, uint16_t length, uint16_t timeout)
72 i2c_address = address;
73 i2cStart(&I2C_DRIVER, &i2cconfig);
74 return i2cMasterReceiveTimeout(&I2C_DRIVER, (i2c_address >> 1), data, length, MS2ST(timeout));
77 uint8_t i2c_writeReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout)
79 i2c_address = devaddr;
80 i2cStart(&I2C_DRIVER, &i2cconfig);
82 uint8_t complete_packet[length + 1];
83 for(uint8_t i = 0; i < length; i++)
85 complete_packet[i+1] = data[i];
87 complete_packet[0] = regaddr;
89 return i2cMasterTransmitTimeout(&I2C_DRIVER, (i2c_address >> 1), complete_packet, length + 1, 0, 0, MS2ST(timeout));
92 uint8_t i2c_readReg(uint8_t devaddr, uint8_t* regaddr, uint8_t* data, uint16_t length, uint16_t timeout)
94 i2c_address = devaddr;
95 i2cStart(&I2C_DRIVER, &i2cconfig);
96 return i2cMasterTransmitTimeout(&I2C_DRIVER, (i2c_address >> 1), regaddr, 1, data, length, MS2ST(timeout));
99 // This is usually not needed. It releases the driver to allow pins to become GPIO again.
100 uint8_t i2c_stop(uint16_t timeout)
102 i2cStop(&I2C_DRIVER);