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esp8266

ESP8266 and “rst cause:2”

So programming the esp8266 through a USB FTDI chip that also supplies the 5V rail, means the chip has less than the 500mA provided by the USB buss. There is probably ~450mA left to power and program the ESP. Based on the data sheets that should be more than enough. Turns out it isn’t.

Apparently writing to flash on the esp8266 has higher power transients than can be supplied by USB alone. I added additional capacitive bypassing on the power rails of two 10uF capacitors to help with high current transients, and powered the board off of an external supply. Doing that and reflashing got my example code working and stopped the flash problems. It definitely stopped the “rest cause:2” resets I was seeing.

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