ESP32: TTGO T-Display + Jtag


I bought a couple of these TTGO T Display modules on BangGood while they were on sales

Perfect to do something more complicated than blink with arduino-cmake-stm32 and our jtag debugger

Hook that to the jtag.... ah, IO14/TMS  is missing. Let's have a look at the datasheet :




Ok, IO14 is used to switch between VBUS / VBAT or something similar. Dont' care,  i dont intend to use the battery module on the board.
So let's remove D6, that the diode on the left here :

and put a dupont wire on the top/left pad.



Open OCD now connects over Jtag.

Comments

  1. raicheaOctober 22, 2020 at 9:23 AM

    I've just been experimenting with a TTGO T-Display and ESP-Prog... I just connected a wire to the end of D6. If you power the ESP32 from USB and then power up the ESP-Prog, it works fine as the state of IO14 is not important in the battery circuit due to the wired-OR formed by the two diodes.

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