ESP8266 Community Forum

Through one header you can load code from the Arduino IDE into the ATMEGA328P or the ESP8266EX.....

Questions? Comments?

Richard.

Hi !

1) not clear for me : who drives ESP8266 GPIO0 ?
Direct access to ESP8266 bootloader still possible or only indirect access through Mega328 and I2C bridge ?
ETX and ERX exposed, no E'GPIO0' ?

2) Besides 'universal programming header' could the board's design evolves and allows 'universal OTA programming' ? (328 ICSP handled optionnaly by ESP8266 ) ?

Regards

Yes universal OTA would be awsome and that is definitelety a goal!

1. nDTR drops and causes the RESET on program header for both IC
2. TX is kept low on GPIO0 by use of the "break" function of RS232 signalling....
3. if the ATMEGA328 boot loader sees a 0xc0 transmitted it knows the ESP8266 is being programmed and keeps silent on the bus, this requires a every so slightly modified boot loader on the 328, which looks for the 0xc0 and pulls itself off the serial bus if it sees it...
4. if the ESP8266 does not see the 0xc0 it also stays silent and allows the ATMEGA328 to be programmed.

Its a symbiotic relationship....

Richard.

soo atmega and esp8266 cant comunicate with serial line right?