4-line LCD Help - using PortA instead of B

[NavMicroSystems]

Arch,

that's what I thought, as it has an embedded 44780.

Assuming Tom has got his hardware wired up properly I don't know how to slove his problem.

[Tom Gonser]

The Mfg sent along this note:


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quote: "All I see are row 1 and 3 with shading, rows 2 and 4 blank, and no text."
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This is a sign that the lcd controller is not initialized. A typical init sequence is:

0x38 [wait 4mS] 0x38 [wait 100uS] 0x38 0x38 0x08 0x01 0x06 0x0C

just like the data sheet shows. Apparently LCDOUT is not performing the init. I think it has an internal flag to keep track of the init, and it probably thinks it doesn't need to do it again. I'm not really familiar with that code.
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Does anyone know how to 'manually send' those commands? What is 0x38, etc?

Tom

[NavMicroSystems]

Tom,

You definitely don't have to worry about "initialisation" with PBP and a 44780 (or compatible),
PBP does it for you.

you have either got a bug in your wiring or your LCD is "dead" (or even both)

[bbarney]

I have to agree with Ralph,you have a short somewhere or bad connection.

[Tom Gonser]

OK, folks. Thanks for the help. I am going to rewire this to another LCD and see what happens. I agree something must have gotten messed up or fried, it just is not that complicated.

Tom

[nomada]

Hi to you all

I remembered that when I implemented Melanie's OLIMPIC TIMER with a Crystal Clear Technology LCD (with Hitachi controller) I couldn't have any character on dispaly until I set pull-ups on the four datas lines to LCD. I don't know if it could solve you problem, but I suppose it won't make things worst. maybe it deserves a try.

Sometimes components...

Have a nice weekend

ps. - lcd from CCT can be bought throw ARROW, they are cheap (!?), we use it in our vending machines and so far so good...

[Bruce]

If you're still using the 18F2525, then you need to change ADCON1 = 7 to ADCON1 = 15 or PortA is setup for A/D inputs, and you'll never get a response from your LCD.