I'm trying to wrap up my RC4 project. It has been over two years now. I recall vividly, now, why I stopped working on it in the first place. It has become far too complicated, and the code has been distilled and compacted to such a degree that there is very little decoupling between routines, so if I so much as tug on one strand, a hundred other strands are disturbed.

It's like a giant tangled web.

And because I developed the firmware entirely in Microchip assembly, it takes a long time to make any significant changes to the code, and there are so many features that it is about impossible to fully test the thing to make sure it still works after I change something. Usually, when I change something - even the smallest of things - I discover weeks or months later that I broke something else in the process.

Anyway, the thing was so close to being in a usable state, that I wanted to finish it. I thought I could knock of a few items on the [HUGE] list of issues in just a few days. Well, it has been just a few days, now, and I have knocked off a couple of items, so I am making progress. It has just been slow-going.

I fixed two problems over the past two days. Each problem took me an entire day to troubleshoot and resolve. It's getting to that point. It seems with all programs - whether desktop applications or embedded drivers - once you get the main framework in and working, there are little details that pop up that need to be addressed. And the longer you work at it, the longer it seems to take to find the last of the details, and the harder it is to wrap up those last few.

Why is that?

I have been thinking of posting my RC4 development journal online as a 'blog of its own, just to give people an idea of what goes into developing a piece of technology (I'm sure some people would be interested in it). Just the journal alone is up to 228 pages as of today. That doesn't include the web documents already online, the technical reference documents I have created, and the source code...and the 10-page list of issues! Fortunately, most of the issues are resolved, now. But there are what seems like hundreds of items still open regarding little details or feature ideas that will never be implemented, or odd little quirky observations that I have made that I wanted to revisit to understand, etc., etc. I have even added to this list over just the past few days. But I am tackling the last few significant issues, of which there are only a small handful.

I think in another week I will have it pretty much wrapped up, at least to a point where I can start using it. I want to put it on my Trike, along with an embedded '386 computer and some sensors, and see what I can do with it. It should be fun.

That reminds me, I got a new power supply for the embedded computer that I was building inside of a power supply case. I installed it and...it exhibited the exact same behavior as the other power supply. I thought these things must be notorious for dying in this peculiar way.

But then something spoke to me. Remember a while back when I burnt up a ribbon cable while trying to connect RC4 to one of my embedded computer boxes? When I did that, the power supply kept trying to come on when the cable was shorted, but it just kept doing this on-off-on-off dance. Well, that's what this new power supply was doing with absolutely nothing connected to it.

I decided maybe there was something on-board that was causing it to shut itself down and maybe there was a short in the supply somewhere. However, after doing some research, I found the specs for this supply and discovered that it has a minimum load requirement in order to work. It needs a minimum 3A load on the +5 outputs, and something like a 0.12A load on the +12V outputs, in order to work!

Geezzz!

So, now I have to figure out how to create a 3A load on the thing so I can test it to see if it works. 3 amps!? The computer only draws 1.5A, max., and I just don't have enough stuff to add to it to bring it up to 3A. I guess I need to add a string of Christmas lights or something. I am thinking it must have on-board protection to shut itself off if there isn't any load on the outputs (at least that is what I am hoping) - there must be some reason it's doing the on-off-on-off dance.

Anyway, here is a shot of where I am working on RC4, now that I am on my big desk instead of the nice little workbench I built when I was in the thick of developing this thing.

I added the shelf with the oscilloscope on it today. Man, the 'scope is getting old I guess, because the trace would not focus very well, and my probes are all messed up. I need some new equipment.

Badly.

That's about it for today. I will be ordering a new round of boards for RC4 next week -- revision G. I can't wait to get them!