Hi all.

I'm trying to retrofit an LCD onto another project. Because of the
shortage in pins, I'm running in 4 bit mode.

After banging my head against a wall for quite a while, I've managed
to come up with the magical delay values that seem to make this
particular module happy (notably different than the already two
different options provided in the two possible controller datasheets,
naturally). I've been using some of Philip Pemberton's great LCD
library (available on the PICList.org website), and I'm gradually
adapting it and writing my own for this particular purpose. The code
is mostly working, so I'm soldiering on in that area.

One thing that's happening is that I think I'm getting glitches on the
enable line to the LCD. At the moment the LCD module is connected to
the board via a number of separate wires about 6" long. While I hope
to make it a bit neater (and shorter) for the final, that is likely
how it will have to go. I think this is upsetting the LCD as I can get
it to reliably fail if I disconnect the lead from my logic analyzer to
the enable pin. So I'd like to help my module attain the kind of
happiness that only reliable operation can provide it.

I have a couple of options here. I'm likely going to make a small PCB
for the LCD to hold the contrast pot, a connector for the wiring
harness back to the main PCB, and the module itself. On that PCB I
could easily add a resistor or cap (or both). On the main PCB I can
add a capacitor or resistor between the enable pin and ground, and I
might be able to add a resistor between the PIC and the enable pin. To
be honest, I wouldn't mind adding at least a 100R resistor on all the
LCD pins in case someone mistakenly tries to send voltage on to the
output pins by accident.

So what might be the best thing for me to do? If it's worthwhile I can
add the same thing for each of the 6 pins on the LCD PCB (enable, RS,
Data4-Data7).

My current plan would be to test out solutions with my current,
extremely bad setup. If it makes things happier now, I would hope it
could only get better with a proper setup.

Thanks!

Josh
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