Re: LCD cable length
I think that the length of the cable depends on the pulse duration to send and receive data from LCD module, cable capacitance and output impedance of the MCU.
If you keep signal durations long enough to overcome the cable capacitance, then the output resistive component of impedance would be the limitation...
My experience which I spent days... ->On my first use of digital humidity and temperature sensor SHT-11 from Sensirion, it didn't give back ack signal. That means it didn't worked. Everything was OK, both the hardware and the software. Finally I realized that the cable impedance and length was the main problem. When it was shortened to an appropriate length, the sensor begin to give responses and worked very well.