T-Beam V1.1 GPS Access

I removed the display as you were replying :slight_smile: still no change. i also was wondering how i may go about using a code that uses the 2nd uart at pins 13 and 14 to send a wakeup command to the AXP (DCDC1)? can anyone help me with this?

The AXP is an I2C connected device which is different to UART. You can custom configure different I2C pins however connecting them physically to the AXP would be difficult. I don’t think you have an issue with pins 21 and 22.

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i suspected as much. in the post i linked to, the user was able to reassign the I2C pins and reawaken the DCDC1 line to the AXP chip?

They changed the I2C pins that the OLED uses so they could power down the OLED while not effecting the original I2C lines to the AXP. The OLED in its default position uses the same 3V3 rail as the ESP32 though so it has power to it when the ESP32 does.

Also out of interest, DCDC1 and DCDC3 outputs appear to be linked to provide the 3V3 rail.

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i missed that tidbit, thank you for educating me! there must be some way to address the AXP!!

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Hello Comms networking guy I’m curious to know where did you buy your Tbeam with the GPS issue? I’m buying Tbeams from the Lilygo channel exclusively, as they are TTGO’s manufacturer themselves. I can recommend buying from Lilygo to avoid hardware related issues. I don’t have any commercial benefits but they are honest and very reactive to feedback for improving their boards. Some parallel outlets are still selling older versions so there might be slight hardware differences.

Purchased from some random seller on Amazon given the long delay for delivery via Aliexpress. Subsequently I have ordered from Lilygo’s store on Aliexpress, but I’m still waiting for the 915 MHz boards. That said the Amazon boards appear to be genuine.

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That’s great! thanks for the update.