generated from hulk/gd32e23x_template_cmake_vscode
rewrite read 16bits
This commit is contained in:
316
Src/i2c.c
316
Src/i2c.c
@@ -156,7 +156,6 @@ i2c_result_t i2c_bus_reset(void) {
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return I2C_RECOVERY_OK;
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}
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#ifdef DEBUG_VERBOSE
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/**
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* @brief 扫描I2C总线，查找连接的设备
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*
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@@ -263,7 +262,6 @@ void i2c_scan(void) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TC) == RESET) {}
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}
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}
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#endif
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i2c_result_t i2c_write_16bits(uint8_t slave_addr, uint8_t reg_addr, uint8_t data[2]) {
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uint8_t state = I2C_STATE_START;
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@@ -429,198 +427,212 @@ i2c_result_t i2c_write_16bits(uint8_t slave_addr, uint8_t reg_addr, uint8_t data
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}
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i2c_result_t i2c_read_16bits(uint8_t slave_addr, uint8_t reg_addr, uint8_t *data) {
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i2c_state_t state = I2C_STATE_START;
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uint16_t timeout = 0;
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uint8_t retry_count = 0;
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bool write_phase = true;
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uint8_t data_index = 0;
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// 参数检查：防止空指针和非法地址
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if (data == NULL || slave_addr > 0x7F) {
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return I2C_RESULT_INVALID_PARAM;
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}
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i2c_state_t state = I2C_STATE_START;
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bool read_cycle = false;
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bool i2c_timeout_flag = false;
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uint16_t timeout = 0;
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uint8_t number_of_byte = 2;
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/* enable acknowledge */
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i2c_ack_config(I2C0, I2C_ACK_ENABLE);
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while (!(i2c_timeout_flag)) {
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while (retry_count < (uint8_t)I2C_MAX_RETRY) {
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switch (state) {
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case I2C_STATE_START:
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if (RESET == read_cycle) {
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/* i2c master sends start signal only when the bus is idle */
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while (i2c_flag_get(I2C0, I2C_FLAG_I2CBSY) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout < I2C_TIME_OUT) {
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/* whether to send ACK or not for the next byte */
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i2c_ackpos_config(I2C0, I2C_ACKPOS_NEXT);
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} else {
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// i2c_bus_reset();
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timeout = 0;
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state = I2C_STATE_START;
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#ifdef DEBUG_VERBOES
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printf("i2c bus is busy in READ!\n");
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#endif
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}
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}
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/* send the start signal */
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i2c_start_on_bus(I2C0);
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timeout = 0;
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// wait for bus to be idle
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while (i2c_flag_get(I2C0, I2C_FLAG_I2CBSY) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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// send start condition
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i2c_start_on_bus(I2C0);
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state = I2C_STATE_SEND_ADDRESS;
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timeout = 0;
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break;
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case I2C_STATE_SEND_ADDRESS:
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/* i2c master sends START signal successfully */
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/* wait for start condition to be sent */
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while ((!i2c_flag_get(I2C0, I2C_FLAG_SBSEND)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout < I2C_TIME_OUT) {
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if (RESET == read_cycle) {
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i2c_master_addressing(I2C0, slave_addr << 1, I2C_TRANSMITTER);
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state = I2C_STATE_CLEAR_ADDRESS;
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} else {
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i2c_master_addressing(I2C0, slave_addr << 1, I2C_RECEIVER);
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i2c_ack_config(I2C0, I2C_ACK_DISABLE);
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state = I2C_STATE_CLEAR_ADDRESS;
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}
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timeout = 0;
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} else {
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timeout = 0;
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state = I2C_STATE_START;
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read_cycle = RESET;
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#ifdef DEBUG_VERBOES
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printf("i2c master sends start signal timeout in READ!\n");
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#endif
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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// send slave address
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if (write_phase) {
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/* write phase: send address with write bit */
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i2c_master_addressing(I2C0, (slave_addr << 1), I2C_TRANSMITTER);
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} else {
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/* read phase: send address with read bit */
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i2c_master_addressing(I2C0, (slave_addr << 1) | 0x01, I2C_RECEIVER);
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}
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state = I2C_STATE_CLEAR_ADDRESS;
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timeout = 0;
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break;
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case I2C_STATE_CLEAR_ADDRESS:
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/* address flag set means i2c slave sends ACK */
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/* wait for address to be acknowledged */
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while ((!i2c_flag_get(I2C0, I2C_FLAG_ADDSEND)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout < I2C_TIME_OUT) {
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/* Check for NACK before clearing address flag */
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if (i2c_flag_get(I2C0, I2C_FLAG_AERR)) {
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/* NACK received - slave did not acknowledge address */
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i2c_flag_clear(I2C0, I2C_FLAG_AERR);
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i2c_stop_on_bus(I2C0);
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#ifdef DEBUG_VERBOES
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printf("i2c NACK received for address 0x%02X in read!\n", slave_addr);
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#endif
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return I2C_RESULT_NACK;
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}
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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i2c_flag_clear(I2C0, I2C_FLAG_ADDSEND);
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if ((SET == read_cycle) && (1 == number_of_byte)) {
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/* send a stop condition to I2C bus */
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i2c_stop_on_bus(I2C0);
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}
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timeout = 0;
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/* clear address flag, address flag set means i2c slave sends ACK */
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i2c_flag_clear(I2C0, I2C_FLAG_ADDSEND);
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if (write_phase) {
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state = I2C_STATE_TRANSMIT_DATA;
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} else {
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timeout = 0;
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state = I2C_STATE_START;
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read_cycle = RESET;
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#ifdef DEBUG_VERBOES
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printf("i2c master clears address flag timeout in READ!\n");
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#endif
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/* 读阶段：配置ACK位置和禁用ACK（针对2字节读取） */
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i2c_ackpos_config(I2C0, I2C_ACKPOS_NEXT);
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i2c_ack_config(I2C0, I2C_ACK_DISABLE);
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state = I2C_STATE_RECEIVE_DATA;
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data_index = 0;
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}
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timeout = 0;
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break;
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case I2C_STATE_TRANSMIT_DATA:
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if (RESET == read_cycle) {
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/* wait until the transmit data buffer is empty */
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while ((!i2c_flag_get(I2C0, I2C_FLAG_TBE)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout < I2C_TIME_OUT) {
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/* send the EEPROM's internal address to write to : only one byte address */
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i2c_data_transmit(I2C0, reg_addr);
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timeout = 0;
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} else {
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timeout = 0;
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state = I2C_STATE_START;
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read_cycle = RESET;
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#ifdef DEBUG_VERBOES
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printf("i2c master wait data buffer is empty timeout in READ!\n");
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#endif
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}
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/* wait until BTC bit is set */
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while ((!i2c_flag_get(I2C0, I2C_FLAG_BTC)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout < I2C_TIME_OUT) {
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timeout = 0;
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state = I2C_STATE_START;
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read_cycle = SET;
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} else {
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timeout = 0;
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state = I2C_STATE_START;
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read_cycle = RESET;
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#ifdef DEBUG_VERBOES
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printf("i2c master sends register address timeout in READ!\n");
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#endif
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}
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} else {
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while (number_of_byte) {
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timeout++;
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if (2 == number_of_byte) {
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/* wait until BTC bit is set */
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while (!i2c_flag_get(I2C0, I2C_FLAG_BTC));
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/* send a stop condition to I2C bus */
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i2c_stop_on_bus(I2C0);
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}
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/* wait until RBNE bit is set */
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if (i2c_flag_get(I2C0, I2C_FLAG_RBNE)) {
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/* read a byte from the EEPROM */
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*data = i2c_data_receive(I2C0);
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/* point to the next location where the byte read will be saved */
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data++;
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/* decrement the read bytes counter */
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number_of_byte--;
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timeout = 0;
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}
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if (timeout > I2C_TIME_OUT) {
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timeout = 0;
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state = I2C_STATE_START;
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read_cycle = 0;
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#ifdef DEBUG_VERBOES
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printf("i2c master sends data timeout in READ!\n");
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#endif
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}
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}
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timeout = 0;
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state = I2C_STATE_STOP;
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/* wait for transmit buffer to be empty */
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while ((!i2c_flag_get(I2C0, I2C_FLAG_TBE)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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/* send register address */
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i2c_data_transmit(I2C0, reg_addr);
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state = I2C_STATE_RESTART;
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timeout = 0;
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break;
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case I2C_STATE_RESTART:
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/* wait for byte transfer complete BTC: Bit Transfer Complete */
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while ((!i2c_flag_get(I2C0, I2C_FLAG_BTC)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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/* generate repeated start condition */
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i2c_start_on_bus(I2C0);
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/* wait for repeated start condition to be sent */
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timeout = 0;
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while ((!i2c_flag_get(I2C0, I2C_FLAG_SBSEND)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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/* send slave address with read bit */
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i2c_master_addressing(I2C0, (slave_addr << 1) | 0x01, I2C_RECEIVER);
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/* switch to read phase */
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write_phase = false;
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state = I2C_STATE_CLEAR_ADDRESS;
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timeout = 0;
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break;
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case I2C_STATE_RECEIVE_DATA:
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/* 等待BTC标志表示第一个字节接收完成 */
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while ((!i2c_flag_get(I2C0, I2C_FLAG_BTC)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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/* 发送STOP条件 */
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i2c_stop_on_bus(I2C0);
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/* 读取第一个字节 */
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data[0] = i2c_data_receive(I2C0);
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/* 等待第二个字节接收完成 */
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timeout = 0;
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while ((!i2c_flag_get(I2C0, I2C_FLAG_RBNE)) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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/* 读取第二个字节 */
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data[1] = i2c_data_receive(I2C0);
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state = I2C_STATE_STOP;
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break;
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case I2C_STATE_STOP:
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/* i2c master sends STOP signal successfully */
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/* wait for stop condition to complete */
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while ((I2C_CTL0(I2C0) & I2C_CTL0_STOP) && (timeout < I2C_TIME_OUT)) {
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timeout++;
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}
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if (timeout < I2C_TIME_OUT) {
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timeout = 0;
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state = I2C_STATE_END;
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i2c_timeout_flag = I2C_OK;
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} else {
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timeout = 0;
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state = I2C_STATE_START;
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read_cycle = 0;
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#ifdef DEBUG_VERBOES
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printf("i2c master sends stop signal timeout in READ!\n");
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#endif
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if (timeout >= I2C_TIME_OUT) {
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state = I2C_STATE_ERROR;
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break;
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}
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/* i2c master sends STOP signal successfully */
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/* success */
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return I2C_RESULT_SUCCESS;
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case I2C_STATE_ERROR:
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/* send stop condition to release bus */
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i2c_stop_on_bus(I2C0);
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retry_count++;
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if (retry_count >= I2C_MAX_RETRY) {
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#ifdef DEBUG_VERBOES
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printf("IIC read failed after %d retries\n", I2C_RETRY_MAX);
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#endif
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return I2C_RESULT_ERROR;
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}
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/* reset state machine for retry */
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state = I2C_STATE_START;
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write_phase = true;
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data_index = 0;
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timeout = 0;
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/* small delay before retry */
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delay_10us(10);
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break;
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default:
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state = I2C_STATE_START;
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read_cycle = 0;
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i2c_timeout_flag = I2C_OK;
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timeout = 0;
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#ifdef DEBUG_VERBOES
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printf("i2c master sends start signal in READ.\n");
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#endif
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break;
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}
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}
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return I2C_RESULT_SUCCESS;
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return I2C_RESULT_TIMEOUT;
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}
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#ifdef DEBUG_VERBOSE
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Block a user