ESP32-S2 Linux串口OTA升级

一、简介

OTA(Over-the-Air Technology )空中下载技术，通过远程网络为设备更新或者升级，本质就是把固件通过WiFi、蓝牙、4G、5G、网线等写到MCU flash里面，最终实现升级。

二、原理

1.终端设备发送需要升级的固件；

2.MCU接收来自终端设备的固件，并写到flash里面；

3.修改引导程序，下次复位启动当前更新的程序。

三、需要配置

ESP32 OTA升级需要配置分区表，可以自定义分区表也可以使用官方配置的分区表。

本文使用官方配置的分区表，操作步骤如下（ESP-IDF 4.4 PowerShell）：

1.进入工程目录

2.执行idf.py menucofig命令

3.配置一下芯片flash大小（根据对应的芯片选择）

4.改成4MB

5.选择分区表

6.选择，一个出厂程序，两个ota程序

7.q退出y保存，配置完成。

四、程序编写

ESP32-OTA源文件

#include "bsp_ota.h"
#include "crc16.h"
#include "esp_log.h"
#include <stdlib.h>
#include <string.h>static const char *TAG = "uart_ota";uint8_t ota_table[2] = {0x0a,0x0a};
static void UART_OTA_Task(void *arg);void UART_Init(uint32_t baud)
{const uart_config_t uart_config = {.baud_rate = baud,.data_bits = UART_DATA_8_BITS,.parity    = UART_PARITY_DISABLE,.stop_bits = UART_STOP_BITS_1,.flow_ctrl = UART_HW_FLOWCTRL_DISABLE,.source_clk = UART_SCLK_APB,};uart_driver_install(UART_NUM,UART_BUFFER_SIZE,UART_BUFFER_SIZE,0,NULL,0);uart_param_config(UART_NUM,&uart_config);uart_set_pin(UART_NUM,UART_TX,UART_RX,UART_PIN_NO_CHANGE,UART_PIN_NO_CHANGE);
}void UART_OTA_Init(void)
{UART_Init(460800);xTaskCreate(UART_OTA_Task,"UART_OTA_Task",1024 * 6,NULL,3,NULL);
}static void OTA_Ack(uint8_t ota_ack)
{ota_table[0] = ota_ack;uart_write_bytes(UART_NUM,ota_table,2);
}static void UART_OTA_Task(void *arg)
{uint8_t  ota_state = 0;uint32_t rx_len = 0;uint16_t crc_value = 0;uint32_t ota_timeout = 0;uint32_t binary_file_length = 0;uint8_t* uart_rx_buf = (uint8_t*) malloc(UART_BUFFER_SIZE);esp_err_t err = ESP_OK;esp_ota_handle_t update_handle = 0;const esp_partition_t *update_partition = NULL;update_partition = esp_ota_get_next_update_partition(NULL);                                         //获取下一个OTA更新的区域err = esp_ota_begin(update_partition,OTA_SIZE_UNKNOWN, &update_handle);                             //安装OTA升级if(err != ESP_OK){ESP_LOGE(TAG, "esp_ota_begin failed!");}bzero(uart_rx_buf,UART_BUFFER_SIZE); ESP_LOGI(TAG, "esp_ota_begin ok!");while(1){rx_len = uart_read_bytes(UART_NUM,uart_rx_buf,UART_BUFFER_SIZE,1000 / portTICK_RATE_MS);        //接收数据if(rx_len > 0) {if(ota_state == OTA_UPGRADE_READY)                                                          {if(uart_rx_buf[0] == 0x55 && uart_rx_buf[1] == 0x66){crc_value = crc16(uart_rx_buf,rx_len - 2);    if((crc_value & 0xff) == uart_rx_buf[rx_len - 2]  && (crc_value >> 8) == uart_rx_buf[rx_len - 1]){OTA_Ack(OTA_DATA_CRC_OK);err  = esp_ota_write(update_handle, (const void *)uart_rx_buf + 2,rx_len - 4);  //往flash写入数据if (err != ESP_OK) {ESP_LOGE(TAG,"Error: esp_ota_write failed! err = 0x%x", err);esp_restart();}binary_file_length += rx_len - 4;ota_timeout = 0;}else{OTA_Ack(OTA_DATA_CRC_ERR);}      }else if(strstr((char*)uart_rx_buf,"finish") != NULL)                           //OTA写结束{   if(esp_ota_end(update_handle) != ESP_OK) {OTA_Ack(OTA_DATA_CRC_ERR);ESP_LOGE(TAG,"esp_ota_end failed!");}else{OTA_Ack(OTA_WRITE_FINISH);err = esp_ota_set_boot_partition(update_partition);if(err != ESP_OK) {ESP_LOGE(TAG,"esp_ota_set_boot_partition failed! err=0x%x",err);}}esp_restart();}            }else if(strstr((char*)uart_rx_buf,"download:") != NULL)                 //收到下载命令，开始进入下载状态{OTA_Ack(OTA_UPGRADE_READY);ota_state = OTA_UPGRADE_READY;}uart_flush_input(UART_NUM);bzero(uart_rx_buf,UART_BUFFER_SIZE); }else if(ota_state == OTA_UPGRADE_READY){ota_timeout++;if(ota_timeout >= 60)                                                   //下载超时，复位单片机{OTA_Ack(OTA_WRITE_TIMEOUT);ESP_LOGI(TAG,"uart ota timeout\n");  esp_restart();}}}free(uart_rx_buf);                                                               //释放内存
}

ESP32-OTA头文件

#ifndef _BSP_OTA_H_
#define _BSP_OTA_H_#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_ota_ops.h"
#include "driver/uart.h"
#include "driver/gpio.h"#define UART_BUFFER_SIZE               (1024 * 4 + 4)#define UART_NUM                       UART_NUM_1
#define UART_TX                        GPIO_NUM_6
#define UART_RX                        GPIO_NUM_7#define OTA_UPGRADE_READY              0x05
#define OTA_DATA_CRC_ERR               0x06
#define OTA_DATA_CRC_OK                0x07
#define OTA_WRITE_TIMEOUT              0x08
#define OTA_WRITE_FINISH       	       0x09void UART_OTA_Init(void);
#endif

LINUX串口应用程序

#include <stdio.h>
#include <netdb.h>
#include <unistd.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <termios.h>
#include <pthread.h>
#include <dirent.h>
#include <arpa/inet.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <string.h>
#include <dirent.h>
#include <semaphore.h>// gcc download.c -o download -pthread			//编译
// ./download /dev/ttyUSB0 app_main.bin			//执行
//  find . -name "*.bin" | xargs rm -f   		删除 /home/lym/workcode目录下所有以.bin结尾的文件static unsigned short const crc16_table[] = {0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
};//查表法,低位在前
unsigned short crc16(unsigned char *pBuffer, unsigned short usDataLen)
{unsigned short i = 0;unsigned short uIndex = 0;unsigned short uCRC16  = 0xffff;for(i = 0;i < usDataLen;i++){uIndex = ((uCRC16 & 0xff) ^ (pBuffer[i] & 0xff));uCRC16 = ((uCRC16 >> 8) & 0xff) ^ crc16_table[uIndex];}return (uCRC16 >> 8)|(uCRC16 << 8);
}#define MAX 					(1024 * 4 + 4)
int firmware_size;
static sem_t sem_handler; #define OTA_UPGRADE_READY              0x05
#define OTA_DATA_CRC_ERR               0x06
#define OTA_DATA_CRC_OK                0x07
#define OTA_WRITE_TIMEOUT              0x08
#define OTA_WRITE_FINISH       	   	   0x09void *read_usart_pthread(void *arg)
{int  rx_len = 0;int  timeout = 0;char rx_buff[255] = {0};float bar_value = 0;									//进度值int send_count = firmware_size / (MAX -  4);			//需要发送次数float value = 1.0 / send_count * 100 ;					//进度条比例，发送一次的值while(1){rx_len = read(*(int*)arg,rx_buff,sizeof(rx_buff));if(rx_len > 0){//if(rx_buff[0] == 0x55 && rx_buff[2] == 0x66)//{switch(rx_buff[0]){case OTA_UPGRADE_READY:{timeout = 0;bar_value = 0;printf("\nesp32-s2 ota ready\n");printf(">>>"); sem_post(&sem_handler);  }break;case OTA_DATA_CRC_ERR:{printf("\ndata crc error!\n");printf("firmware write error!\n");return (void*)0;}break;case OTA_DATA_CRC_OK:{timeout = 0;bar_value += value;if(bar_value <= 99.9){printf("\b\b\b>>>>>");   		//'\b'把前面输出的覆盖printf("%.0f%%",bar_value);}fflush(stdout);						//清空缓冲区}break;case OTA_WRITE_FINISH:{printf("\b\b\b\b>>>>>");   			//'\b'把前面输出的覆盖printf("100%%\n");printf("firmware write finish!\n");return (void*)0;}break;case OTA_WRITE_TIMEOUT:{printf("firmware write timeout\n");return (void*)0;}break;default:{//rx_buff[rx_len] = 0;//printf("%s",rx_buff);printf(".");fflush(stdout);						//把数据从缓冲区输出到窗口}break;}//}}else{timeout++;if(timeout >= 20000){printf("\nconnect esp32-s2 timeout!\n");system("killall download");}usleep(100);}memset(rx_buff,0,sizeof(rx_buff));}return (void*)0;
}int main(int argv,char *argc[])
{int ret;int file_fd;int tty_fd;DIR *dir;struct stat stat_buf;struct termios options;struct dirent *entry;char buff[MAX] = {0};char temp[20] = {0};unsigned short crc;pthread_t tid;sem_init(&sem_handler,0,0);											//创建一个线程间的信号量/*dir = opendir(".");													//打开当前目录if(dir == NULL){perror("opendir  error");goto clean;}while((entry = readdir(dir)) != NULL)								//获取目录下的所有文件{if(strstr(entry->d_name,".bin") != NULL)						//判断是否是bin文件{printf("entry->d_name:%s\n",entry->d_name);break;}}*/if(argv < 2){printf("function input parameter error\n");return -1;}printf("firmware version：%s\n",argc[2]);file_fd = open(argc[2],O_RDONLY);									//以只读的方式打开文件if(file_fd < 0){perror("open file error");return file_fd;}memset(&stat_buf,0,sizeof(stat_buf));ret = fstat(file_fd, &stat_buf);									//获取文件信息if(ret < 0){perror("fstat file error");goto clean;}firmware_size = stat_buf.st_size;printf("firmware size：%ld bytes\n",stat_buf.st_size);if(stat_buf.st_size <= 0){perror("file szie error");goto clean;}tty_fd = open(argc[1],O_RDWR|O_NOCTTY|O_NDELAY) ; 					//打开串口if(tty_fd < 0){printf("open %s error\n",argc[1]);goto clean;}memset(&options,0,sizeof(options)) ;ret = tcgetattr(tty_fd,&options); 									//获取原有的串口属性的配置if(ret != 0){perror("tcgetattr error") ;goto clean;}options.c_cflag |= (CLOCAL|CREAD );   								//CREAD 开启串行数据接收，CLOCAL并打开本地连接模式options.c_cflag &= ~CSIZE;											//先使用CSIZE做位屏蔽  options.c_cflag |= CS8; 											//设置8位数据位options.c_cflag &= ~PARENB; 										//无校验位cfsetispeed(&options,B460800);										//设置460800波特率cfsetospeed(&options,B460800);options.c_cflag &= ~CSTOPB;											//设置一位停止位options.c_oflag &= ~OPOST;											//解决发送数据中有OA = 0D 0A的问题options.c_cc[VMIN]  = 0; 											//非规范模式读取时的最小字符数tcflush(tty_fd,TCIOFLUSH);   										//清空输入输出缓存tcsetattr(tty_fd, TCSANOW, &options);   							//设置终端控制属性,TCSANOW：不等数据传输完毕就立即改变属性if((tcsetattr(tty_fd, TCSANOW,&options))!=0){perror("tcsetattr error");goto clean ;}ret = pthread_create(&tid,NULL,read_usart_pthread,(void*)&tty_fd);if(ret) {perror("pthread_create error");goto clean;}printf("connect esp32-s2");sprintf(temp,"download:%ld",stat_buf.st_size);write(tty_fd,temp,sizeof(temp));									//发送下载请求 + 固件大小	sem_wait(&sem_handler);  											//堵塞等待信号量tcflush(tty_fd,TCIOFLUSH);   										//清空输入输出缓存sleep(1);while(1){buff[0] = 0x55;buff[1] = 0x66;ret = read(file_fd,buff + 2,MAX - 4);if(ret <= 0){break;}crc = crc16(buff,ret + 2);buff[ret + 2] = crc & 0xff;buff[ret + 3] = crc >> 8;ret = write(tty_fd,buff,ret + 4);memset(buff,0,MAX);usleep(1000 * 200);}sleep(1);write(tty_fd,"finish",sizeof("finish"));pthread_join(tid,NULL);sem_destroy(&sem_handler);clean:closedir(dir);close(file_fd);close(tty_fd);return 0;
}

五、验证

1.接线：CH340-TX 接 ESP32-S2 RX(GPIO7) CH340-RX 接 ESP32-S2 TX(GPIO6)；

2.编译下载