635 and a Parallax Javelin Stamp


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Intelligent Serial LCD Modules 635 - 20x4 RS-232/TTL-Serial Interface

I would like to use this LCD and keypad to make a communicating thermostat for my home heating system.

I plan on using a parallax Javelin Stamp module to control everything (I like C++ and Java)

Everything I see on the boards shows using this the way it was intended to be connected to a PC.

I am unable to locate a complete PDF for this module (found the 634full.pdf)

Does anyone have any code, pointers showing using the Keys on this Keypad for processing?

I pretty much want to retrieve the user pushing Up Arrow or Down Arrow to raise or lower the temperature
and will use the Side Arrows, Check Button and X button for other features.

Is it possible using the Javelin to receive the input from the pressed keys? I do not want this device to do anything; I will handle the presses and display the output.

ANY help ANY one?
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CF Support2

For the Serial CFA635 series, start off by taking a look at the data sheet -- you can find the one for the variant that you are wanting to use here:


We also have our 635_WinTest software that has the source code available for it. The software accesses the functionality of the module, to include button presses. You can download the 635_WinTest and the source code from here:


The primary difference in the Serial and USB versions is that the Serial version has the RS-232 daughter board, and one set of GPIO lines is given up so that the serial version supports 3 fans headers on the SCAB instead of all 4. Other than that, the serial and USB versions are the same in functionality and communications.