Page 1 of 1

ESP8266 bootloader/programming mode

Posted: Mon Oct 15, 2018 5:25 pm
by Erik84750
To get ESP8266 in programming mode GPIO 00 must be pulled low on start-up.
I use DTR from a serial interface to obtain this low pulse, which also is used to reset the MCU. So when the serial interface wants to start writing, it sends a low through DTR which is used to pull low CH_PD as well as GPIO 00. CH_PD goes high before GPIO 00 is allowed high (through hardware).
However, when GPIO 00 had been programmed as an output, and it happens to be high, there is no way I can use this DTR to pull GPIO 00 low.
Is there any work-around that allows the ESP8266 to be programmed "on-the-fly" with GPIO 00 as an output in high state?
Grts,
Erik