Entering automatic bootloader with esp32_devkitc (without using usb)
Posted: Fri Sep 20, 2019 11:37 am
I am trying to program an esp32_devkitc v4 without using the usb port - we have developed a pcb around an esp32 and I would like to know that I can program the devkitc reliably over serial as proof of concept before I try the pcb.
I connected EN and GPIO0 directly to RTS and DTR pins of a usb-serial adaptor (https://ebay.us/Feqgyp) but it doesn't flash. If I press 'Boot' button it does work which implies EN/RTS is working but GPIO0/DTR part is the problem.
I tried using the transistors circuit as in devkitc (https://dl.espressif.com/dl/schematics/ ... v4-sch.pdf) but it didn't work at all, and the esptool documentation (https://github.com/espressif/esptool/wi ... bootloader) implies this is only needed if NOT using esptool. I am using IDF v3.2.2.
I connected EN and GPIO0 directly to RTS and DTR pins of a usb-serial adaptor (https://ebay.us/Feqgyp) but it doesn't flash. If I press 'Boot' button it does work which implies EN/RTS is working but GPIO0/DTR part is the problem.
I tried using the transistors circuit as in devkitc (https://dl.espressif.com/dl/schematics/ ... v4-sch.pdf) but it didn't work at all, and the esptool documentation (https://github.com/espressif/esptool/wi ... bootloader) implies this is only needed if NOT using esptool. I am using IDF v3.2.2.