What display for Midipal?

#1

Hi,
simple question, what displays do some of you use for th emidipal I assambled 2 of those with different newhaven displays, it seems like on my scope I can see some logic signals like clock or data in coming fromt he Atmel IC to the display , but it wont work.

I read something about it must be a 3V3 supply type, I got some with 5V some with 3V3, I tested both, but neither works, then Ic hecked the pinning and the Newhaven displays use mirrored Vcc and GND pins, so it wont fit to the PCB, can that be true or did I simply confuse something badly.

Anyway maybe I shorted out one display or something is indeed wrong on the PCB.

Thanks for your help, if someone got a working midipal please could you if possible send me an exact display type.

I am using those:
NHD-0108BZ-RN-YBW-33V
Pin1: VSS=GND Pin2: VDD=3V3

NHD-0108BZ-FSY-YBW-33V3
same pin asignment

I switched the pinning for testing, either i killed something, but the supply voltage seems correct, or i am confused, just need little tip into right direction.
Help appreciated :slight_smile:

#2

Does the display show anything? When its not picking up the communication from the microcontroller, it shows a black line and a white line.
If you don’t see them or if the screen is entirely black or entirely white, you should adjust the contrast trimmer.

#3

I build a midipal on perfboard a long time ago and I also found out the hard way that some of these displays use a different pin out. Your displays are probably broken.
For the smd version you should use the 3v3 one. I think if you search the forum you will find the correct display somewhere. Otherwise use waybackmachine to search the diy midipal page on old MI site.

#4

It should be NHD-0108BZ-FSY-YBW-33V3-ND

info from here