UART TX low level voltage does not drop all the way to ground

DarioPellegrini · January 1

Hello, I am trying to get my CrowDisplay 5" to communicate via serial.
If I push some data on the TX line everything seems fine, but as soon as I attach the pins to another UART interface (eg an ESP32) the low level does not drop all the way to ground, but stays at around 1.6V, not enough to be detected.

Setup:

TX disconnected, low level matches ground:

TX connected, low level remains at 1.6V:

Any idea on what is causing this problem and what I could do to solve it?
Thank you!

Jennie · January 16

Dear ，
Please try to remove this cable

UART TX low level voltage does not drop all the way to ground

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