Society of Robots - Robot Forum

General Misc => Misc => Topic started by: baxter on June 20, 2011, 04:56:32 PM

Title: Using an old graphics card as a MPU?
Post by: baxter on June 20, 2011, 04:56:32 PM
Please forgive me but I have no experience with robotics... yet. My girlfriend's gonna hate this. My question is about using a graphics card as a micro-controller for a robot. I mean an older one of course. I tried to look it up already but couldn't find any reference to it. I'm assuming that means it won't work but I'm dying to know why it won't. It's got it's own CPU, ram, I/O etc. Is the voltage the problem? Or something else I've missed? I would love someone who knows to tell me why this can't work. It's the only way I learn. lol.

Like I said, I'm very new.  Thanks guys.

Title: Re: Using an old graphics card as a MPU?
Post by: corrado33 on June 20, 2011, 06:23:57 PM
In my very uneducated opinion, I think you'd have trouble programming the thing. 

It's already on a board, the chips are pretty hard to desolder, then you'd have to find a datasheet, figure out how everything else in the board is connected to it, etc etc.

And, I'm guessing it wouldn't be a reprogrammable chip...

I'd say too much work.  Buy a chip made for hobbyists. 

Then again, I really don't know what I'm talking about.  But those are the reason's I wouldn't attempt the project unless I saw that it could be done.  (I'm no electrical engineer, I won't be pioneering new ways to do anything in the field... trust me.)
Title: Re: Using an old graphics card as a MPU?
Post by: garrettg84 on June 21, 2011, 05:46:10 AM
As corrado stated, the gfx card won't work as a micro-controller, especially an older one. Graphics cards are very specific types of processors, it wasn't until recently that graphics cards came with general purpose cores (think CUDA). If you are trying to use the old graphics card due to cost, take a look at the TI launchpad. The TI launchpad can be had for $4.30 shipped from TI's website.
Title: Re: Using an old graphics card as a MPU?
Post by: baxter on June 21, 2011, 07:59:01 AM
As corrado stated, the gfx card won't work as a micro-controller, especially an older one. Graphics cards are very specific types of processors, it wasn't until recently that graphics cards came with general purpose cores (think CUDA). If you are trying to use the old graphics card due to cost, take a look at the TI launchpad. The TI launchpad can be had for $4.30 shipped from TI's website.

Thanks to both of you. I guess I thought you guys had some easy fix for reprogramming chips. I had no idea the chips were that cheap. Great. I have another question though... I'm planning to scrap a bunch of older computers and printers for parts and I hate throwing things out. Is there anything I should be on the lookout for? I'm guessing capacitors, printer motors and wire. Anything else you guys can think of?

Thanks,

I appreciate the help
Title: Re: Using an old graphics card as a MPU?
Post by: garrettg84 on June 21, 2011, 10:45:58 AM
Is there anything I should be on the lookout for? I'm guessing capacitors, printer motors and wire. Anything else you guys can think of?

I would try to keep the power supplies intact. The computer power supplies can be turned into decent bench power supplies: http://www.instructables.com/id/ATX--%3E-Lab-Bench-Power-Supply-Conversion/ (http://www.instructables.com/id/ATX--%3E-Lab-Bench-Power-Supply-Conversion/)

As for the rest of the parts, you pretty well nailed it. On modern computers, there aren't really all that many parts to scavenge for an entry level hobby. The other bit, you might actually keep the old computers intact as well. Some of them can make decent linux based machines for robotics control.