generated from hulk/gd32e23x_template_cmake_vscode
640 lines
23 KiB
C
640 lines
23 KiB
C
//
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// Created by dell on 24-12-20.
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// Improved I2C driver with better state machine and error handling
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//
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#include "i2c.h"
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/* Private variables */
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static uint8_t i2c_retry_count = 0;
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/*!
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\brief configure the GPIO ports
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\param[in] none
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\param[out] none
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\retval none
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*/
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void i2c_gpio_config(void) {
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/* enable IIC GPIO clock */
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rcu_periph_clock_enable(RCU_GPIO_I2C);
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/* connect I2C_SCL_PIN to I2C_SCL */
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gpio_af_set(I2C_SCL_PORT, I2C_GPIO_AF, I2C_SCL_PIN);
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/* connect I2C_SDA_PIN to I2C_SDA */
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gpio_af_set(I2C_SDA_PORT, I2C_GPIO_AF, I2C_SDA_PIN);
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/* configure GPIO pins of I2C */
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gpio_mode_set(I2C_SCL_PORT, GPIO_MODE_AF, GPIO_PUPD_PULLUP, I2C_SCL_PIN);
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gpio_output_options_set(I2C_SCL_PORT, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ, I2C_SCL_PIN);
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gpio_mode_set(I2C_SDA_PORT, GPIO_MODE_AF, GPIO_PUPD_PULLUP, I2C_SDA_PIN);
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gpio_output_options_set(I2C_SDA_PORT, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ, I2C_SDA_PIN);
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}
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/*!
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\brief configure the I2CX interface
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\param[in] none
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\param[out] none
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\retval i2c_status_t
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*/
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i2c_status_t i2c_config(void) {
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/* configure I2C GPIO */
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i2c_gpio_config();
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/* enable I2C clock */
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rcu_periph_clock_enable(RCU_I2C);
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/* configure I2C clock */
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i2c_clock_config(I2C0, I2C_SPEED, I2C_DTCY_2);
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/* configure I2C address - use 0x00 as master doesn't need specific address */
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i2c_mode_addr_config(I2C0, I2C_I2CMODE_ENABLE, I2C_ADDFORMAT_7BITS, I2C_MASTER_ADDRESS);
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/* enable I2CX */
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i2c_enable(I2C0);
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/* enable acknowledge */
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i2c_ack_config(I2C0, I2C_ACK_ENABLE);
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/* reset retry counter */
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i2c_retry_count = 0;
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return I2C_STATUS_SUCCESS;
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}
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/*!
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\brief reset I2C bus with proper 9-clock recovery
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\param[in] none
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\param[out] none
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\retval i2c_status_t
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*/
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i2c_status_t i2c_bus_reset(void) {
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uint8_t i;
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/* disable I2C peripheral */
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i2c_disable(I2C0);
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i2c_deinit(I2C0);
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/* configure SDA/SCL as GPIO output for manual control */
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gpio_mode_set(I2C_SCL_PORT, GPIO_MODE_OUTPUT, GPIO_PUPD_PULLUP, I2C_SCL_PIN);
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gpio_mode_set(I2C_SDA_PORT, GPIO_MODE_OUTPUT, GPIO_PUPD_PULLUP, I2C_SDA_PIN);
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gpio_output_options_set(I2C_SCL_PORT, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ, I2C_SCL_PIN);
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gpio_output_options_set(I2C_SDA_PORT, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ, I2C_SDA_PIN);
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/* ensure both lines are high initially */
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gpio_bit_set(I2C_SCL_PORT, I2C_SCL_PIN);
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gpio_bit_set(I2C_SDA_PORT, I2C_SDA_PIN);
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delay_10us(I2C_DELAY_10US);
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/* generate 9 clock pulses to release any stuck slave */
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for (i = 0; i < I2C_RECOVERY_CLOCKS; i++) {
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gpio_bit_reset(I2C_SCL_PORT, I2C_SCL_PIN);
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delay_10us(I2C_DELAY_10US);
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gpio_bit_set(I2C_SCL_PORT, I2C_SCL_PIN);
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delay_10us(I2C_DELAY_10US);
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}
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/* generate stop condition */
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gpio_bit_reset(I2C_SDA_PORT, I2C_SDA_PIN);
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delay_10us(I2C_DELAY_10US);
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gpio_bit_set(I2C_SCL_PORT, I2C_SCL_PIN);
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delay_10us(I2C_DELAY_10US);
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gpio_bit_set(I2C_SDA_PORT, I2C_SDA_PIN);
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delay_10us(I2C_DELAY_10US);
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/* reconfigure as I2C pins */
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gpio_af_set(I2C_SCL_PORT, I2C_GPIO_AF, I2C_SCL_PIN);
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gpio_af_set(I2C_SDA_PORT, I2C_GPIO_AF, I2C_SDA_PIN);
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gpio_mode_set(I2C_SCL_PORT, GPIO_MODE_AF, GPIO_PUPD_PULLUP, I2C_SCL_PIN);
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gpio_mode_set(I2C_SDA_PORT, GPIO_MODE_AF, GPIO_PUPD_PULLUP, I2C_SDA_PIN);
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/* reconfigure the I2CX interface */
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return i2c_config();
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}
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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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* 该函数会扫描I2C总线上的所有地址（1到126），并尝试与每个地址进行通信。
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* 如果在某个地址上发现了设备，则会打印出该设备的地址。
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* 最后会打印出找到的设备总数。
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*/
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void i2c_scan(void) {
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uint32_t timeout;
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uint8_t address;
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int found_devices = 0;
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// printf("Scanning I2C bus...\r\n");
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const char* msg1 = "Scanning I2C bus...\r\n";
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for (uint8_t i = 0; msg1[i] != '\0'; i++) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, msg1[i]);
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}
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TC) == RESET) {}
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for (address = 1; address < 127; address++) {
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timeout = 0;
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// 生成起始条件
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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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if (timeout >= I2C_TIME_OUT) {
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continue; // 超时，跳过该地址
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}
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i2c_start_on_bus(I2C0);
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timeout = 0;
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// 等待起始条件发送完成
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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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if (timeout >= I2C_TIME_OUT) {
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continue; // 超时，跳过该地址
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}
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i2c_master_addressing(I2C0, (address << 1), I2C_TRANSMITTER);
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timeout = 0;
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// 等待地址发送完成
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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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if (timeout < I2C_TIME_OUT) {
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i2c_flag_clear(I2C0, I2C_FLAG_ADDSEND);
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// printf("Found device at 0x%02X\r\n", address);
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const char* msg2_prefix = "Found device at 0x";
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for (uint8_t i = 0; msg2_prefix[i] != '\0'; i++) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, msg2_prefix[i]);
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}
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// 发送地址的十六进制表示
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uint8_t hex_chars[] = "0123456789ABCDEF";
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, hex_chars[(address >> 4) & 0x0F]);
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, hex_chars[address & 0x0F]);
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const char* msg2_suffix = "\r\n";
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for (uint8_t i = 0; msg2_suffix[i] != '\0'; i++) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, msg2_suffix[i]);
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}
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TC) == RESET) {}
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found_devices++;
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}
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// 生成停止条件
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i2c_stop_on_bus(I2C0);
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timeout = 0;
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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 (found_devices == 0) {
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// printf("No I2C devices found.\r\n");
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const char* msg3 = "No I2C devices found.\r\n";
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for (uint8_t i = 0; msg3[i] != '\0'; i++) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, msg3[i]);
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}
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TC) == RESET) {}
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} else {
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// printf("Total %d I2C devices found.\r\n", found_devices);
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const char* msg4_prefix = "Total ";
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for (uint8_t i = 0; msg4_prefix[i] != '\0'; i++) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, msg4_prefix[i]);
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}
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// 发送设备数量
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if (found_devices >= 10) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, '0' + (found_devices / 10));
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}
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, '0' + (found_devices % 10));
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const char* msg4_suffix = " I2C devices found.\r\n";
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for (uint8_t i = 0; msg4_suffix[i] != '\0'; i++) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, msg4_suffix[i]);
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}
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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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/*!
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\brief write 16-bit data to I2C device with improved state machine
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\param[in] slave_addr: 7-bit slave address
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\param[in] reg_addr: register address
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\param[in] data: pointer to 2-byte data array
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\param[out] none
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\retval i2c_status_t
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*/
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i2c_status_t i2c_write_16bits(uint8_t slave_addr, uint8_t reg_addr, const uint8_t data[2]) {
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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 data_index = 0;
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uint8_t retry_count = 0;
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/* Parameter validation */
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if (data == NULL || slave_addr > 0x7F) {
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return I2C_STATUS_INVALID_PARAM;
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}
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/* Enable acknowledge */
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i2c_ack_config(I2C0, I2C_ACK_ENABLE);
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while (retry_count < I2C_MAX_RETRY) {
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switch (state) {
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case I2C_STATE_START:
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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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/* 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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state = I2C_STATE_ERROR;
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break;
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}
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/* Send slave address with write bit */
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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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timeout = 0;
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break;
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case I2C_STATE_CLEAR_ADDRESS:
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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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state = I2C_STATE_ERROR;
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break;
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}
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/* Clear address flag */
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i2c_flag_clear(I2C0, I2C_FLAG_ADDSEND);
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state = I2C_STATE_TRANSMIT_REG;
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timeout = 0;
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break;
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case I2C_STATE_TRANSMIT_REG:
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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_TRANSMIT_DATA;
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timeout = 0;
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data_index = 0;
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break;
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case I2C_STATE_TRANSMIT_DATA:
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/* Wait for byte 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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/* Send data bytes */
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if (data_index < 2) {
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i2c_data_transmit(I2C0, data[data_index]);
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data_index++;
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timeout = 0;
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/* Stay in this state until all data is sent */
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} else {
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/* All data sent, proceed to stop */
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state = I2C_STATE_STOP;
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timeout = 0;
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}
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break;
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case I2C_STATE_STOP:
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/* Send stop condition */
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i2c_stop_on_bus(I2C0);
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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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state = I2C_STATE_ERROR;
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break;
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}
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/* Success */
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return I2C_STATUS_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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/* Increment retry counter */
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retry_count++;
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if (retry_count >= I2C_MAX_RETRY) {
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#ifdef DEBUG_VERBOSE
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// printf("I2C write failed after %d retries\r\n", I2C_MAX_RETRY);
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const char* msg5_prefix = "I2C write failed after ";
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for (uint8_t i = 0; msg5_prefix[i] != '\0'; i++) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, msg5_prefix[i]);
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}
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, '0' + I2C_MAX_RETRY);
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const char* msg5_suffix = " retries\r\n";
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for (uint8_t i = 0; msg5_suffix[i] != '\0'; i++) {
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
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usart_data_transmit(I2C_DEBUG_UART, msg5_suffix[i]);
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}
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while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TC) == RESET) {}
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#endif
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return I2C_STATUS_TIMEOUT;
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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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timeout = 0;
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data_index = 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_ERROR;
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break;
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}
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}
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return I2C_STATUS_TIMEOUT;
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}
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/*!
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\brief read 16-bit data from I2C device with improved state machine
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\param[in] slave_addr: 7-bit slave address
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\param[in] reg_addr: register address
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\param[out] data: pointer to 2-byte data buffer
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\retval i2c_status_t
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*/
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i2c_status_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 data_index = 0;
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uint8_t retry_count = 0;
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bool write_phase = true; /* First phase: write register address */
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/* Parameter validation */
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if (data == NULL || slave_addr > 0x7F) {
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return I2C_STATUS_INVALID_PARAM;
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}
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/* Enable acknowledge */
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i2c_ack_config(I2C0, I2C_ACK_ENABLE);
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while (retry_count < I2C_MAX_RETRY) {
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switch (state) {
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case I2C_STATE_START:
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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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/* Configure ACK position for 2-byte read */
|
||
if (!write_phase) {
|
||
i2c_ackpos_config(I2C0, I2C_ACKPOS_NEXT);
|
||
}
|
||
|
||
/* Send start condition */
|
||
i2c_start_on_bus(I2C0);
|
||
state = I2C_STATE_SEND_ADDRESS;
|
||
timeout = 0;
|
||
break;
|
||
|
||
case I2C_STATE_SEND_ADDRESS:
|
||
/* Wait for start condition to be sent */
|
||
while ((!i2c_flag_get(I2C0, I2C_FLAG_SBSEND)) && (timeout < I2C_TIME_OUT)) {
|
||
timeout++;
|
||
}
|
||
if (timeout >= I2C_TIME_OUT) {
|
||
state = I2C_STATE_ERROR;
|
||
break;
|
||
}
|
||
|
||
/* Send slave address */
|
||
if (write_phase) {
|
||
/* Write phase: send address with write bit */
|
||
i2c_master_addressing(I2C0, (slave_addr << 1), I2C_TRANSMITTER);
|
||
} else {
|
||
/* Read phase: send address with read bit */
|
||
i2c_master_addressing(I2C0, (slave_addr << 1) | 0x01, I2C_RECEIVER);
|
||
/* Disable ACK for last byte */
|
||
i2c_ack_config(I2C0, I2C_ACK_DISABLE);
|
||
}
|
||
state = I2C_STATE_CLEAR_ADDRESS;
|
||
timeout = 0;
|
||
break;
|
||
|
||
case I2C_STATE_CLEAR_ADDRESS:
|
||
/* Wait for address to be acknowledged */
|
||
while ((!i2c_flag_get(I2C0, I2C_FLAG_ADDSEND)) && (timeout < I2C_TIME_OUT)) {
|
||
timeout++;
|
||
}
|
||
if (timeout >= I2C_TIME_OUT) {
|
||
state = I2C_STATE_ERROR;
|
||
break;
|
||
}
|
||
|
||
/* Clear address flag */
|
||
i2c_flag_clear(I2C0, I2C_FLAG_ADDSEND);
|
||
|
||
if (write_phase) {
|
||
state = I2C_STATE_TRANSMIT_REG;
|
||
} else {
|
||
/* For single byte read, send stop after clearing address */
|
||
if (data_index == 1) {
|
||
i2c_stop_on_bus(I2C0);
|
||
}
|
||
state = I2C_STATE_RECEIVE_DATA;
|
||
data_index = 0;
|
||
}
|
||
timeout = 0;
|
||
break;
|
||
|
||
case I2C_STATE_TRANSMIT_REG:
|
||
/* Wait for transmit buffer to be empty */
|
||
while ((!i2c_flag_get(I2C0, I2C_FLAG_TBE)) && (timeout < I2C_TIME_OUT)) {
|
||
timeout++;
|
||
}
|
||
if (timeout >= I2C_TIME_OUT) {
|
||
state = I2C_STATE_ERROR;
|
||
break;
|
||
}
|
||
|
||
/* Send register address */
|
||
i2c_data_transmit(I2C0, reg_addr);
|
||
state = I2C_STATE_RESTART;
|
||
timeout = 0;
|
||
break;
|
||
|
||
case I2C_STATE_RESTART:
|
||
/* Wait for byte transfer complete */
|
||
while ((!i2c_flag_get(I2C0, I2C_FLAG_BTC)) && (timeout < I2C_TIME_OUT)) {
|
||
timeout++;
|
||
}
|
||
if (timeout >= I2C_TIME_OUT) {
|
||
state = I2C_STATE_ERROR;
|
||
break;
|
||
}
|
||
|
||
/* Switch to read phase */
|
||
write_phase = false;
|
||
state = I2C_STATE_START;
|
||
timeout = 0;
|
||
break;
|
||
|
||
case I2C_STATE_RECEIVE_DATA:
|
||
if (data_index < 2) {
|
||
if (data_index == 1) {
|
||
/* Wait for BTC before sending stop for last byte */
|
||
while ((!i2c_flag_get(I2C0, I2C_FLAG_BTC)) && (timeout < I2C_TIME_OUT)) {
|
||
timeout++;
|
||
}
|
||
if (timeout >= I2C_TIME_OUT) {
|
||
state = I2C_STATE_ERROR;
|
||
break;
|
||
}
|
||
/* Send stop condition before reading last byte */
|
||
i2c_stop_on_bus(I2C0);
|
||
}
|
||
|
||
/* Wait for receive buffer not empty */
|
||
while ((!i2c_flag_get(I2C0, I2C_FLAG_RBNE)) && (timeout < I2C_TIME_OUT)) {
|
||
timeout++;
|
||
}
|
||
if (timeout >= I2C_TIME_OUT) {
|
||
state = I2C_STATE_ERROR;
|
||
break;
|
||
}
|
||
|
||
/* Read data byte */
|
||
data[data_index] = i2c_data_receive(I2C0);
|
||
data_index++;
|
||
timeout = 0;
|
||
|
||
if (data_index >= 2) {
|
||
state = I2C_STATE_STOP;
|
||
}
|
||
} else {
|
||
state = I2C_STATE_STOP;
|
||
}
|
||
break;
|
||
|
||
case I2C_STATE_STOP:
|
||
/* Wait for stop condition to complete */
|
||
while ((I2C_CTL0(I2C0) & I2C_CTL0_STOP) && (timeout < I2C_TIME_OUT)) {
|
||
timeout++;
|
||
}
|
||
if (timeout >= I2C_TIME_OUT) {
|
||
state = I2C_STATE_ERROR;
|
||
break;
|
||
}
|
||
|
||
/* Success */
|
||
return I2C_STATUS_SUCCESS;
|
||
|
||
case I2C_STATE_ERROR:
|
||
/* Send stop condition to release bus */
|
||
i2c_stop_on_bus(I2C0);
|
||
|
||
/* Increment retry counter */
|
||
retry_count++;
|
||
if (retry_count >= I2C_MAX_RETRY) {
|
||
#ifdef DEBUG_VERBOSE
|
||
// printf("I2C read failed after %d retries\r\n", I2C_MAX_RETRY);
|
||
const char* msg6_prefix = "I2C read failed after ";
|
||
for (uint8_t i = 0; msg6_prefix[i] != '\0'; i++) {
|
||
while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
|
||
usart_data_transmit(I2C_DEBUG_UART, msg6_prefix[i]);
|
||
}
|
||
while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
|
||
usart_data_transmit(I2C_DEBUG_UART, '0' + I2C_MAX_RETRY);
|
||
const char* msg6_suffix = " retries\r\n";
|
||
for (uint8_t i = 0; msg6_suffix[i] != '\0'; i++) {
|
||
while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TBE) == RESET) {}
|
||
usart_data_transmit(I2C_DEBUG_UART, msg6_suffix[i]);
|
||
}
|
||
while (usart_flag_get(I2C_DEBUG_UART, USART_FLAG_TC) == RESET) {}
|
||
#endif
|
||
return I2C_STATUS_TIMEOUT;
|
||
}
|
||
|
||
/* Reset state machine for retry */
|
||
state = I2C_STATE_START;
|
||
write_phase = true;
|
||
timeout = 0;
|
||
data_index = 0;
|
||
|
||
/* Small delay before retry */
|
||
delay_10us(10);
|
||
break;
|
||
|
||
default:
|
||
state = I2C_STATE_ERROR;
|
||
break;
|
||
}
|
||
}
|
||
|
||
return I2C_STATUS_TIMEOUT;
|
||
}
|
||
|
||
/*!
|
||
\brief get status string for debugging
|
||
\param[in] status: i2c_status_t value
|
||
\param[out] none
|
||
\retval const char* status string
|
||
*/
|
||
const char* i2c_get_status_string(i2c_status_t status) {
|
||
switch (status) {
|
||
case I2C_STATUS_SUCCESS:
|
||
return "SUCCESS";
|
||
case I2C_STATUS_TIMEOUT:
|
||
return "TIMEOUT";
|
||
case I2C_STATUS_NACK:
|
||
return "NACK";
|
||
case I2C_STATUS_BUS_BUSY:
|
||
return "BUS_BUSY";
|
||
case I2C_STATUS_ERROR:
|
||
return "ERROR";
|
||
case I2C_STATUS_INVALID_PARAM:
|
||
return "INVALID_PARAM";
|
||
default:
|
||
return "UNKNOWN";
|
||
}
|
||
}
|