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 follows the convention of the AVR i2c_master library.
19 * As a result addresses are expected to be already shifted (addr << 1).
20 * I2CD1 is the default driver which corresponds to pins B6 and B7. This
22 * Please ensure that HAL_USE_I2C is TRUE in the halconf.h file and that
23 * STM32_I2C_USE_I2C1 is TRUE in the mcuconf.h file.
26 #include "i2c_master.h"
30 static uint8_t i2c_address;
32 // This configures the I2C clock to 400Mhz assuming a 72Mhz clock
33 // For more info : https://www.st.com/en/embedded-software/stsw-stm32126.html
34 static const I2CConfig i2cconfig = {
35 STM32_TIMINGR_PRESC(15U) |
36 STM32_TIMINGR_SCLDEL(4U) | STM32_TIMINGR_SDADEL(2U) |
37 STM32_TIMINGR_SCLH(15U) | STM32_TIMINGR_SCLL(21U),
44 palSetGroupMode(GPIOB,6,7, PAL_MODE_INPUT); // Try releasing special pins for a short time
45 chThdSleepMilliseconds(10);
47 palSetPadMode(GPIOB, 6, PAL_MODE_ALTERNATE(4) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_PUPDR_PULLUP);
48 palSetPadMode(GPIOB, 7, PAL_MODE_ALTERNATE(4) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_PUPDR_PULLUP);
50 //i2cInit(); //This is invoked by halInit() so no need to redo it.
53 // This is usually not needed
54 uint8_t i2c_start(uint8_t address)
56 i2c_address = address;
57 i2cStart(&I2C_DRIVER, &i2cconfig);
61 uint8_t i2c_transmit(uint8_t address, uint8_t* data, uint16_t length, uint16_t timeout)
63 i2c_address = address;
64 i2cStart(&I2C_DRIVER, &i2cconfig);
65 return i2cMasterTransmitTimeout(&I2C_DRIVER, (i2c_address >> 1), data, length, 0, 0, MS2ST(timeout));
68 uint8_t i2c_receive(uint8_t address, uint8_t* data, uint16_t length, uint16_t timeout)
70 i2c_address = address;
71 i2cStart(&I2C_DRIVER, &i2cconfig);
72 return i2cMasterReceiveTimeout(&I2C_DRIVER, (i2c_address >> 1), data, length, MS2ST(timeout));
75 uint8_t i2c_writeReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout)
77 i2c_address = devaddr;
78 i2cStart(&I2C_DRIVER, &i2cconfig);
80 uint8_t complete_packet[length + 1];
81 for(uint8_t i = 0; i < length; i++)
83 complete_packet[i+1] = data[i];
85 complete_packet[0] = regaddr
87 return i2cMasterTransmitTimeout(&I2C_DRIVER, (i2c_address >> 1), complete_packet, length + 1, 0, 0, MS2ST(timeout));
90 uint8_t i2c_readReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout)
92 i2c_address = devaddr;
93 i2cStart(&I2C_DRIVER, &i2cconfig);
94 return i2cMasterTransmitTimeout(&I2C_DRIVER, (i2c_address >> 1), regaddr, 1, data, length, MS2ST(timeout));
97 // This is usually not needed. It releases the driver to allow pins to become GPIO again.
98 uint8_t i2c_stop(uint16_t timeout)
100 i2c_address = address;
101 i2cStop(&I2C_DRIVER);