Songhe Mega2560+ESP8266模块WiFiEsp初始化失败求助

硬件环境 #

• Songhe Mega2560 + WiFi R3 Mega2560 + ESP8266 4MB内存集成板

测试代码（上传至Mega2560） #

用于通过Serial3与ESP8266通信测试固件：

#include "WiFiEsp.h"

// Emulate Serial3 on pins 6/7 if not present
#ifndef HAVE_HWSERIAL3
#include "SoftwareSerial.h"
SoftwareSerial Serial3(6, 7); // RX, TX
#endif

void setup() {
  // initialize serial for debugging
  Serial.begin(115200);
  // initialize serial for ESP module
  Serial3.begin(115200);
  // initialize ESP module
  WiFi.init(&Serial3);

  // check for the presence of the shield
  if (WiFi.status() == WL_NO_SHIELD) {
    Serial.println("WiFi shield not present");
    // don't continue
    while (true);
  }

  // Print WiFi MAC address
  printMacAddress();
}

void loop() {
  // do nothing
}

串口监视器输出 #

刷写多款AT固件后，串口始终返回超时错误：

22:28:07.009 -> [WiFiEsp] Initializing ESP module
22:28:08.023 -> [WiFiEsp] >>> TIMEOUT >>>
22:28:10.026 -> [WiFiEsp] >>> TIMEOUT >>>
22:28:12.022 -> [WiFiEsp] >>> TIMEOUT >>>
22:28:14.023 -> [WiFiEsp] >>> TIMEOUT >>>
22:28:16.020 -> [WiFiEsp] >>> TIMEOUT >>>
22:28:17.006 -> [WiFiEsp] Cannot initialize ESP module
22:28:23.017 -> [WiFiEsp] >>> TIMEOUT >>>
22:28:23.017 -> [WiFiEsp] No tag found
22:28:23.017 -> WiFi shield not present

刷写与测试步骤 #

1. 将DIP开关5、6、7拨至ON，其余拨至OFF，将RXD/TXD切换至RXD0
2. 通过USB线将电脑COM3端口连接至集成板
3. 使用esptool.py刷写ESP8266固件：
   • 下载Espressif官方ESP8266-IDF-AT_V2.2.1.0固件，使用factory_WROOM-02.bin写入地址0
   • 执行命令：esptool.py --chip auto --port COM3 --baud 115200 --before default_reset --after hard_reset write_flash -z --flash_mode dio --flash_size 4MB 0x0 factory_WROOM-02.bin
4. 断开USB线
5. 将DIP开关1、2、3、4拨至ON，其余拨至OFF，将RXD/TXD切换至RXD3
6. 连接USB线，通过Arduino IDE上传代码并查看串口监视器

固件刷写命令及输出（刷写成功） #

C:\Users\[MY NAME]\Downloads\ESP8266_NONOS_SDK-3.0.5\ESP8266_NONOS_SDK-3.0.5\bin>esptool.py write_flash --flash_mode dout --flash_size 4MB-c1 0x0 boot_v1.7.bin 0x01000 at/1024+1024/user1.2048.new.5.bin 0x1fb000 blank.bin 0x1fc000 esp_init_data_default_v08.bin 0xfe000 blank.bin 0x1fe000 blank.bin
esptool.py v4.4
Found 1 serial ports
Serial port COM3
Connecting....
Detecting chip type... Unsupported detection protocol, switching and trying again...
Connecting....
Detecting chip type... ESP8266
Chip is ESP8266EX
Features: WiFi
Crystal is 26MHz
MAC: a4:e5:7c:b6:77:c0
Uploading stub...
Running stub...
Stub running...
Configuring flash size...
Flash will be erased from 0x00000000 to 0x00000fff...
Flash will be erased from 0x00001000 to 0x00065fff...
Flash will be erased from 0x001fb000 to 0x001fbfff...
Flash will be erased from 0x001fc000 to 0x001fcfff...
Flash will be erased from 0x000fe000 to 0x000fefff...
Flash will be erased from 0x001fe000 to 0x001fefff...
Flash params set to 0x0360
Compressed 4080 bytes to 2936...
Wrote 4080 bytes (2936 compressed) at 0x00000000 in 0.4 seconds (effective 92.5 kbit/s)...
Hash of data verified.
Compressed 413556 bytes to 296987...
Wrote 413556 bytes (296987 compressed) at 0x00001000 in 26.2 seconds (effective 126.1 kbit/s)...
Hash of data verified.
Compressed 4096 bytes to 26...
Wrote 4096 bytes (26 compressed) at 0x001fb000 in 0.1 seconds (effective 373.3 kbit/s)...
Hash of data verified.
Compressed 128 bytes to 75...
Wrote 128 bytes (75 compressed) at 0x001fc000 in 0.1 seconds (effective 11.8 kbit/s)...
Hash of data verified.
Compressed 4096 bytes to 26...
Wrote 4096 bytes (26 compressed) at 0x000fe000 in 0.1 seconds (effective 365.1 kbit/s)...
Hash of data verified.
Compressed 4096 bytes to 26...
Wrote 4096 bytes (26 compressed) at 0x001fe000 in 0.1 seconds (effective 357.1 kbit/s)...
Hash of data verified.

Leaving...
Hard resetting via RTS pin...

求助内容 #

刷写完成后，使用Arduino串口透传代码（将Serial1替换为Serial3）测试，发送AT指令无响应。尝试过多个版本AT固件，波特率设置为115200，仍无法初始化WiFiEsp模块，求问题原因及解决方法。

内容的提问来源于stack exchange，提问作者Jarhatz