Cheap UART/Serial LCD?

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Anyone know where I can find a really low cost Uart/Serial LCD Module? something like 2x16, or even 1x16. Everything I have seen is around $20 or more.
I found some for around $9, but they have an 8bit parallel data line with 4 control pins, I want to try and keep it as little pins as possible :?
Does anyone make anything in the $10 range or less?

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Most of those character LCD:s with 8bit parallel data usually support 4bit parallel mode as well. If that's good enough for you, you should check datasheet to make sure they support it.

I have bought old mobile phone graphical LCDs with resolution of around 100x65 for 1-2 euros each (for example Siemens C55/A55 LCD - 1euro 90 cents in our local electronics store). 3.3V, controlled via SPI and are really easy interface with.

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A few euros gets you one of these:

http://ledsee.com/index.php?page...

Either accept that you need to drive it in 4 bit mode (so about 8-9 pins in total) or just stick a $1 ATTiny on the back to operate as an intelligent controller (a so called "serial backpack" - try a thread search here) and then interface this to your main AVR with a low pin count interface like 1-wire, I2C, SPI or UART

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There's also a way to drive these with a latch chip, such that you only need three wires plus power.
You have clock, data, and reset, and you're clocking in the status of four data bits plus the control pins.

It's slower of course, but it does save I/O pins.

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timojaask wrote:
Most of those character LCD:s with 8bit parallel data usually support 4bit parallel mode as well. If that's good enough for you, you should check datasheet to make sure they support it.

I have bought old mobile phone graphical LCDs with resolution of around 100x65 for 1-2 euros each (for example Siemens C55/A55 LCD - 1euro 90 cents in our local electronics store). 3.3V, controlled via SPI and are really easy interface with.

a LCD like this spec.

16x2 4bbit and 8bit paralel mode was 4,5$ in my country.
:D
maybe this would be help you :)

Quote:

Tel : 62-21-6293455

Fax : 62-21-6594185

Tel : 62-21-62200530

http://OK-elektronik.com

http://DT-51.com

Email : info@OK-elektronik.com

ArcticSoul
Industrial Electronic Engineering, College Student

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I think the OP was looking for a serial interface to the LCD, kind of like the "serial backpack" mentioned in an earlier post.
Good advice to save money, use the 4 bit mode on your micro or use another smaller chip just for the LCD. It would have to have a UART if you can only use the UART serial mode.

I'll believe corporations
are people when Texas executes one.

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This company has Seiko LCDs 16x2 for $3.00:
http://www.shopeio.com/inventory...

I have been buying surplus lots of LCD character displays on eBay: 5-8 at a time. The last lot that I bought was six for $5 but only half of them worked.

I always use the 4-bit mode and I tie the R/W line to ground. That gives a six line interface with RS on bit 0, E on bit 1, and data4-7 on bits 2 through 5. I have to shift the four bits of each write to align them but this is only two LSL instructions in assembler. The biggest difficulty that I've had using LCDs is getting them initialized correctly. None of the 'canned' procedures offered in the LCD libraries seem to work for me correctly. I always have to do an endless amount of 'diddling the delay values' to get the silly things displaying characters in a predictable and repeatable manner. With LCD character displays, I use a Tiny24 or a Mega8/48/88/168 AVR.
Be wary of using the backlight as it can consume a lot of current. Some advanced character modules have LED backlights that use only 10-15 milliamps and are readable in standard room lighting. If you can find a source of those for $3-$4 each in lots of 100 or more, leave a note here and we can organize a group buy.

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Simonetta wrote:

Be wary of using the backlight as it can consume a lot of current.

Indeed, my current project, a network tester, has a Megga 644, an ENC28J60 and a 20x4 LCD, all running at 3.3v.

With just the AVR it draws about 25ma, adding the ENC28J60, pushes that to about 140ma, the LCD adds about another 5ma. However turn on the backlight and this climbs to 350ma, needless to say I'm going to put this on a switch, to try and save battery life :(

Cheers.

Phill.