Little ATMEGA8-friendly LCD display with breadboard pluggable pins

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I have a breadboard, ATMEGA8 and some buttons. ATMEGA8 doesn't have much pins so I would like to buy a cheap little LCD display that uses SPI which I can simply plug into my breadboard.

Example:

Picture of an 11 pin LCD module with an SD card slot

This one on the picture has a PCB with a soldered SD card slot and it is brutally expensive!

On eBay, I found some displays like that under $5 that I like, but they have some tape-like wires that I have no idea how to connect to anything. I have no idea should I even try soldering that. I don't want to make smoke and dust out of it.

 

Requirements:

Maximum price = $7

Minimum resolution = 128x160

Minimum color bits = 16

Aspect ratio = 3:4 or 4:3

Pin spacing = 2mm

EDIT: Pin spacing = 2.54mm (I measured it wrongly in the first place, sorry)

Backlight

Last Edited: Thu. Feb 12, 2015 - 10:51 PM
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2mm pin spacing is going to be a problem.

 

Most Ebay modules are 2.54mm spacing to match a regular breadboard.

 

Note that bare TFT displays are 3.3V.   The modules that come with a pcb and 2.54mm header pins may or may not have a 5V -> 3.3V level-shifters.

 

David.

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How about LCD modules with female pin sockets like on the breadboard? I can connect the breadboard with the sockets with jumpers.

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I use the 1.8" 160x128 TFT screens found on eBay for about $5-7 (including shipping).  I always get the ones with the ST7735 controller and I always use the Adafruit Arduino library.  I've used five and they all work OK.  They have the eight pin header  (Vcc +5v, Gnd, SC-enable, Reset, data/cmd, MOSI data, serial clock, LED).  I use the SPI option (Arduino D9 for Data/cmd, D10 for SC enable, AVR reset for TFT reset, D11 for MOSI, D13 for SCK, no resistor on LED, Vcc +5v) on the Arduino Nano.

 

The touch screen 320x240 TFTs are a little more expensive, but they can be difficult to get to work since the little Chinese companies that sell them on eBay provide either no or essentially useless documentation.  These TFT screens can any of five different controller ICs.  Even though they all use SPI (a few use one 8-bit parallel port [Arduino D2-D8] and a few Analog pins), the user still needs to initialize the controllers by sending 40-60 bytes that set up all the configuration registers in the TFT controller IC.  This can be hit-or-miss if you don't know which controller IC that the TFT module is using, or if you select a library that doesn't use the exact set of configuration values for the particular combination of TFT screen and controller IC that the eBay company chose to send to you.  Even TFT modules that appear nearly identical can be very different internally.  And if you take them apart then they will remain non-functionally broken because the controller ICs are in the very fragile 'Chip-on-glass' interface format to the screen section.

 

That's why I continue to use the somewhat obsolete 1.8" 160x128 ST7735 units.

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Is the driver GPL? If yes, then I'm screwed. I hate GPL! Is there a MIT driver or public domain driver? Is it possible to make my own driver by reading a documentation for that ST7735 controller?

 

And what do you think about this http://www.ebay.com/itm/2-2-Seri... ?

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Why are you worried about GPL ?

 

There are many libraries for a ST7735R controller.

Likewise,   for an ILI9341 or ILI9340C.

 

None of the boards that you have shown use 2mm headers.

They use 2.54mm headers that are compatible with breadboards (or jumper cables)

 

Yes,   you can buy connectors, jumpers,  ribbons,  ... for 2mm.    They are less common and cost more.

 

Note that the ILI9340C board in your last link is a 3.3V module.    There are similar style ST7735R red modules.

 

David.

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Why are you worried about GPL ?

presumably because of the "derived work" requirement to publish your own source that links to any GPL code. But usually this is a barrier to commercial, not academic use.

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david.prentice wrote:

Why are you worried about GPL ?

 

There are many libraries for a ST7735R controller.

Likewise,   for an ILI9341 or ILI9340C.

 

None of the boards that you have shown use 2mm headers.

They use 2.54mm headers that are compatible with breadboards (or jumper cables)

 

Yes,   you can buy connectors, jumpers,  ribbons,  ... for 2mm.    They are less common and cost more.

 

Note that the ILI9340C board in your last link is a 3.3V module.    There are similar style ST7735R red modules.

 

David.

I measured the breadboard holes again and realized it was 2.54mm already. So that problem is out.

On which voltage levels does ATMEGA8 work and which board has those voltage levels? I don't want to use resistors on every single pin I use. I don't have enough space. Neither do I want to burn anything.

clawson wrote:

Why are you worried about GPL ?

presumably because of the "derived work" requirement to publish your own source that links to any GPL code. But usually this is a barrier to commercial, not academic use.

Yeah. I want my work to be under my license.