I have found this interesting board selling on Aliexpress website. It is an Arduino Mega 2650 with a built-in ESP8266 which allows the Mega to connect to wifi. This board has cut down a lot of wiring and bring out interesting possibilities. One of this is to connect up both the microcontrollers using ESP-link firmware. I have an earlier blog post that described how to wire up an ESP-01 and Arduino Pro Mini. One of the tricky parts in this setup is the sequence of flashing the ESP firmware. Flashing the onboard ESP8266 requires some setting changes to the dip switches. The following are the sequences which I get both the microcontrollers to talk to each other. Set the jumper 5,6,7 to ON and the rest OFF. This will set the ESP to update mode. I am using version 3.0.14 and flashed the ESP using the following parameters: esptool --port com26 --baud 230400 write_flash -fm dio -fs 4MB -ff 80m 0x0 boot_v1.6.bin 0x1000 user1.bin 0x3fc000 esp_init_data_defa...
An old techie.
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