27 Nov 2005 The Swirling Brain   » (Master)

Well, last night I made a multitasking scheduler for a pic16f84 chip. It took about two hours. Why? I don't know, I guess I just wanted to. The problems I ran into were first of all I did a google search and didn't find any PIC multitasking kernel code or OS out there. Second, PICs can't push or pop to the stack. It has an inaccessible hardware stack for calls and interrupts only. That makes it aweful hard to have an interrupt switch processes since you can't play with the return stack. So, my solution was to make a scheduler instead. A scheduler is different than a real process switch because it's not seamless. A process has to "give up" control rather than let an interrupt "take" control to switch processes. But if you can tolerate that then it works ok I guess. An interrupt is running which ticks down sleep timers every ms, but that's about all the interrupt does right now. I have the following process functions: add_process, kill_process, & sleep. I wrote a quick program that starts a blinking LED process then kills itself leaving the LED blinking process to continue running. The kernel currently allows up to 5 processes to run, but I probably have data space to add a few more processes if need be. I compiled it and it's about 300 bytes but I could probably trim it some more if need be. That leaves plenty of room for some useful code. I hope to use the kernel for either some robot code or an RBS controller. I'm still trying to figure out how I can make the interrupt take control of a process, switch to another process and give back control later, but without PUSH and POP or stack access, I'm not sure it can be done other than to use a scheduler type scheme instead.

Well so far the part time job I previously spoke of is NOT a go. I went for my first day, and I did everything that the guy asked me to do, but the computer wasn't very forgiving. For example, he couldn't load some software so he asked me to do it. Well I couldn't load it either so that didn't look good on me. A few other things he couldn't do I couldn't either. He would give me a dead-pan look as if I was doing him wrong or talk condescendingly to me as if I was an idiot. Finally, I was ready to quit when I stood up and started with the, "I'm sorry it's not working out" thing. He interrupted me trying to save the situation with a to-do list of stuff he wanted, but I pretty much already had made up my mind. Anyway, I think that it was sort of mutual, he didn't really seem to like me and I didn't really like him much either. I'm sort of hoping he doesn't call me to come back again but that's still a possiblity. It doesn't look like he will since it's been a while. I'll probably tell him I'm not interested if he does call. Come to think of it, when I first talked to him, he told me about all of his previous computer guys that quit him for other jobs. I'm not thinking that wasn't a coincidence anymore. Not having a computer job for a couple of years now has sort of broken my confidence and that didn't help much. It probably IS me, I don't know. I just know I'm not interested in working with him anymore. In my heart of hearts, though, I know what I'm doing with computers so I don't really worry about it. Good luck to him and hopefully he won't call me back.

Well, at the RBS craft fair I only sold a few RBSs. Enough to make my money back and some, but not enough to justify all the work I had to put into it. I think I'll try one or two more craft fairs, but really ebay seems to be the only thing that works. I've sold a couple more RBSs on ebay, but nothing too exciting. I was hoping it would take off as it got closer to Christmas, but it hasn't really. Oh well.

On the food stamp deal, I found out that they put another $210 on the card. They said they would drop next month to $100 and then cancel it Jan or Feb because I wouldn't do the stupid 40 hours of community service a week * 4 weeks for $100 or 2 a month of food stamps. I'm still looking for a job and doing odd jobs around, but I'm basically ignoring TEC. They're help programs really aren't help, they're a hindrance and interrupted me or blocked me from actually doing the odd job I do have so I won't go to them anymore for their "help." They also told me go drive across city to some job fairs only to find out when I got their, they gave me bad info and the job fairs they recommended weren't there at all - a complete waste of time, energy, and gas money. A good portion of their info seems to nonsensical or outdated and useless. One of their grand suggestions for searching for a job was cold call through the yellow pages companies for an interview. Now I'm not an employment expert, but I would think it would have been better to promote services like head-hunters or job-websites than cold phone calling companies. I mean why waste your time with companies if you don't even have a clue that they may be hiring. I guess you could call thousands of companies before one may say yes we're hiring but nothing with your expertise. Seemed like very ignorant advice to me, but like I said I'm no employment expert.

Well, My dad and mom helped me film the wedding video. Now I just have to edit it and deliver it. Hope that goes well. I really need to get it done like a week before Christmas. I think I can.

I've been working on the Emergent Behavior comics. So far only a couple of comments from readers and all positive. I did also get a request to mention it in a magazine. That was very encouraging!

Somehow our finances have been holding out. I've been tracking it in MS Money and it consistently stays about two to three months out before tanking into the red. I have some theories: either God is graciously blessing me richly or torturing me slowly and terribly, or perhaps a little of both. :-) You decide. I shouldn't joke, but you know I can't explain it so it must be God helping me out somehow even through the trials! As streamlined as our finances are, I'm thinking whenever a good job does come back around our finances will be going through the roof!

Movies? Saw the corpse bride. I didn't care much for it, but Bethany like it. Madagascar. Can't say I finished watching it, but there again, the girls loved it. The Prophecy: Forsaken. It was a TV movie with some smut and weird religion thrown together. Garbage basically, but it did have a couple swirling brain moments what I could endure through.

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