Stephen's Weblog

Oh, finally…

So, this post is a little bit late as well, I almost didn’t manage to make this work :) I’ve been now tinkering with writing a USB device stack for my USB stick for literally the past two weeks now; Being a new space, I’m used to the idea of having issues, but between incredibly stupid bugs, very minimal documentation, and errors in some critical hardware documentation, this has been quite a challenging project.

On the plus side, I now have my USB stick behaving as a virtual com port – so it will be trivial to write extensions and make it start to do really useful stuff (haven’t quite got around to that yet, so expect a part 3)

Additionally, in the process I’ve become pretty familiar with  how USB works, and I’ll try to more simply define it for those who are interested in getting started.

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Well, it was my intention to talk about USB in more detail today, but my USB project has been a little sidetracked – today I wrote the majority of my USB Device implementation but am still stuck debugging a hardware feature that’s not quite working how I think it should… I have a pretty good understanding of USB now from this project, but do actually want to make sure all of my assertions hold before documenting it ;)

So, nothing too interesting this week; Next week should be good though. (and the week after, and the week after. I have quite a bit lined up now, just not all done yet)

Another week has gone by already? Well, I do at least have something to show for it.

So the thing I spent the most spare time on this last week has been designing a FPGA-based PCI card. This is something I’ve wanted to do for some time now (and have an earlier unfinished attempt that was far more complex), but I have recently encountered some inspiration for a board that will be somewhat useful, or at least interesting.

This board isn’t really much of anything special, but it will fill a specific niche, and will be sufficient to try out a lot of interesting things I’ve been thinking of in the PCI space.

So, This isn’t going to be an exceptionally impressive post, but I did collect screenshots from various stages of the board’s development, and  I’ll also discuss the design decisions behind this board.

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Hi again,

As promised, this week’s project entry is much less entertaining;

I did attempt to get this project a bit further today but distractions have taken their toll. Expect this one to come up again in the future :)

So, not too long ago I had the bright idea to build a little USB stick; My motives at the time were apparently highly questionable, so I am here about a month later with a fairly limited use USB stick

One of my major goals behind this project was to have an excuse to work out the details of USB, and try some stuff out, which I’m still doing now. Once I get that done with, I will attempt to explain just how all that works; USB is a bit elaborate, but it’s increasingly interesting and important these days, as serial and parallel ports are becoming more rare. I have another project along these lines too, but it’s quite a bit more low-level.

For this post though, I’m just talking about the hardware design of this project. (more…)