Need help finding embedded CPU

kevbo

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Sep 14, 2003
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Hi, I wasn't sure what place to post this, so it may be a little off topic, but it sort of has to do with CPU's. (If you know a better place to ask about this, please let me know.)

I'm looking for a free (or very cheap) embedded type evaluation board and CPU. It will eventually be used for gathering outdoor temperature data and will transfer to a desktop computer. Here's the jist of what I want.

CPU - anything over 2MHz, preferably RISC, but I don't really care, as most code will be done in C. (I've used the motorolla 68HC11 before, but I believe they cost $).

Memory on board - I may only need 8K, but over 16K would be great.

Input - I'll want to set up 2 or 3 buttons just to set a clock and various other things. I also want a place to hookup a temperature sensor.

Output - need 2 binary outputs to hook some wires to. need a small LCD screen, maybe 2 lines of 16 chars. It would be great if there was an easy way to hook the board up via serial to a desktop, but then I'll have to figure out how to get raw data from it (build a driver?). 2 or 3 LEDs would be nice too.

That's all I can think of now. Does anyone know where I can get something like this for fairly cheap? I've heard of companies giving out evaluation boards, but don't know who does this. I don't need high quality parts or anything, it's more of a self project (and a Birthday present once it's done.)

----- end question, begin ramblings ----

For those who are curious, I just want to collect temperature data, save the data with a time stamp in memory (possibly holding data for a few days at a time until upload.), then every once in awhile, upload the data to desktop, where I can parse the data and put it into a database with a nice interface for looking at temperature variations, maybe some nice graphs and such. So on the board, I will need to be able to set the time (thus some buttons), and then press a button when I want to upload and clear the memory. I may also have an option of how often to save the temperature data in memory.

I'm going to look for a temperature sensor that can be attached to a long (weatherproof) wire to go outside. For uploading, I hope to be able to get raw data from a serial line, but I don't know how to do that yet. Another idea I had (a dirty hack, just an idea, bear with me here), is to take apart a mouse, connect two wires from the board to where the mouse buttons attach to a wire, and simulate left and right mouse clicks (highjack the mouse driver, not sure about the voltages used though??). then I would just have a GUI in python or something to gather my unary encoded data from the clicks, and parse that for the info. I have reason to believe that won't work, but it may be worth a try :)

Thanks for any help or direction.
 

Snorkius

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Sep 16, 2003
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One solution is scrounging an old 'puter. I realise that an old pentium is overkill for what you need, and prolly too big, but it's 100% free. You could also look around for an old palm. You can get some pretty cheap, used ones.

<font color=blue>If the <font color=yellow>laurel</font color=yellow> is to big for your head, it becomes a hoola-hoop, and you have to keep your butt really busy.</font color=blue>
 

kevbo

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The problem with a pentium is that I wouldn't know how to hook up the little LCD, wiring, LEDs and everything. I'm thinking more embedded stuff so that I can wire it how I want. I looked around a little and found something close to what I want. Here's some examples:

<A HREF="http://www.keil.com/boards" target="_new">http://www.keil.com/boards</A>

I was looking at the first one there, the MCBXC167 Evaluation Board. I'm not sure if I can hook a small 32 character LCD to it though. And stuff like this is a LOT easier to program than a pentium. Ever done assembler for a pentium? Not fun. I'm still looking around for a good evaluation board.

Again, if someone knows a good place to ask about these things, let me know. Thanks.
 

Kelledin

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Bumping a rather oldish thread here...but might I suggest a LART board?

They're StrongARM SA-1100 boards with a lot of custom-wireable connections. They consume only a few watts of power and typically run Linux or NetBSD. You can get KSB and Ethernet add-ons for it as well, so you can turn it into a very minimalist workstation complete with video, audio, IDE drives, USB, and networking.

It's quite common to see one powered off a generic battery...it's quite a fun little toy, if you're a hobbyist engineer. :smile:

<A HREF="http://www.lart.tudelft.nl/" target="_new">http://www.lart.tudelft.nl/</A>

Also, there's the Balloon project, which is kind of the next step after the LART. It's based on the more recent SA-1110 CPU and has similar power requirements. However, it's in pretty constant revision and should probably be considered an "alpha" product at this point.

<A HREF="http://www.balloonboard.org/" target="_new">http://www.balloonboard.org/</A>

These aren't exactly all THAT cheap, but they're liable to be cheaper than anything else you'll find. The proprietary stuff (like Intel's IQ80310 kit) costs much more and isn't necessarily all that engineer-friendly.

<i><Lionel Hutz> I'll be defending...The SCO Group!!!??? Even if I lose, I'll be famous!</i><P ID="edit"><FONT SIZE=-1><EM>Edited by kelledin on 12/14/03 11:24 PM.</EM></FONT></P>