Wiring LCD to Futurlec AVR Starter Board

Do you have a link for the manual for this board ?

What CPU does this board use ??

donald

Is the board one of these ??

donald

They don't seem to have the manual online but this is the board:

and this the Stamp (Atmega 128) that it uses:

The link states "UPDATED".

Does this mean you have this board or the older board ?

Do you have a paper manual ?

Can you scan part of the schematic with 14 pin connector ?

The pics on this link does not show any 14 pin Dual Row connectors.

donald

You should read the HD44780 manual. It can communicate in nibble or byte mode.

Map out the AVR port pins to the LCD low (or high) nibble

used

No, you can't. You still need to read from registers.

used

This manual shows RW grounded:

donald

It's possible to operate a character LCD in "write only" mode but you'll need to ensure that you always wait the maximum spec'd time between sending individual characters.

ed

In 4-bit mode you'd wire port D7-D4 to display D7-D4, and then wire port D3, D2 and D1 to display E, R/W and RS (in any order you want, unless you're restricted by existing code). And yes, I'm pretty sure you can hard-wire R/W low and just delay the specified amount after each write to the device.

Mike

Thanks Donald, no paper manual, just a PDF on the CD. I'm not sure why they don't put it online, you'd think it might help sales.

In 4-bit mode you'd wire port D7-D4 to display D7-D4, and then wire port D3, D2 and D1 to display E, R/W and RS (in any order you want, unless you're restricted by existing code). And yes, I'm pretty sure you can hard-wire R/W low and just delay the specified amount after each write to the device.

Mike

Thanks Mike, much clearer now.

As Mike has said, knowing the pinout of the 14 pin connector and the pinout of the LCD display and the link I posted, this should be enough information to get something working.

good luck

donald

PS: Post the manual to a.b.s.e.

Stamp:

Development Board:

OK, thanks.

I see that ETT also wired RW to ground.

So please tell me, whats the problem ??

donald

I forgot to mention the LCD contrast line that also has to go to the display. But I'm sure they've wired everything up to that 14-pin connector the obvious way, so you should just need to provide a 14-pin cable to the display, and then confirm which port bits they're using for E, R/W and RS, and you should be set to write the code to drive the display.

Mike

I forgot to mention the LCD contrast line that also has to go to the display. But I'm sure they've wired everything up to that 14-pin connector the obvious way, so you should just need to provide a 14-pin cable to the display, and then confirm which port bits they're using for E, R/W and RS, and you should be set to write the code to drive the display.

Mike

I had assumed the 14 pin socket would be identical to the 14 pin connector on the LCD. But I found the schematic after Donald had asked about it and the pairs seem reversed. This does not make sense, am I missing something?

Socket:

LCD:

Unless I'm mistaken, this is an artifact of the way the pins on the AVR board header get routed to the wires in the ribbon cable by the female cable connector. I think you'll find the ribbon cable wires up the natural way on the display end, but double check to make sure. Just confirm that AVR GND goes to display GND and AVR +5 to display +5 before you turn on the power. If those are good then all the lines should be good.

Mike

I have the same board, and the schematic is WRONG, That's right! pins ar reversed but not on all headers. Go figure

You get what you pay for. Here is what came with the board:

If anyone has the Protel file or a good working schematic please post

Thanks B