Use Arduino to read LCD screen off pins

Using Arduino Project Guidance
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I am building a test fixture to check if another control board is working correctly. The other board has an LCD screen output. I am wondering if I could attach the arduino in parallel and have it read what the LCD is displaying to verify whether the control board is working properly.

Control board front:

Control board LCD:

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Sure, as long as there are no outputs needed from the LCD.
We used to use the serial ports on a PC as a protocol analyzer to monitor the traffic between two devices so we could monitor the transmit line from both devices.

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