Flecko

Thanks for the quick reply Thorsten. I have plenty of experience with asm. I just wasn't sure, from a technical point of view, if it was possible. I'll just need to do alot more research now before I actually start on this project. If it ever comes to fruition, I'll be sure to post about it here. Thanks again! -Flecko

Hello all, I recently had a crazy idea about programming my PIC, using a bootloader, from an EEPROM. I've never even attempted to write a bootloader before, and so its new territory for me. I've read over Microchips bootloader paper in PDF format, and its somewhat confusing. ( http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en012031 ) See, I would like to be able to burn my programs to an EEPROM, and then 'plug' them into my PIC system and have it program itself from there. The problem is, I don't know if this can technically work. Does anyone here have any bootloader programming experience? I'm all ears as to whether this will work. Thanks everyone, -Flecko

Well, the pic was unharmed. Not sure about my SID or my LCD yet, but at least the circuit works again, despite my stupidity. I thnk from now on I'll have some safety diodes in place. Thanks everyone, -Flecko

Nope, never needed to before. Its just the 7805 running power straight into my circuit. I'm an idiot. Hopefully the negative side of the ac didn't hurt my circuit. Otherwise, I was thinking this might not be so bad. -Flecko

I accidentally hooked an AC power supply(13v, 200ma) up to my PIC project. It is running into a 7805. The system seemed to be getting power, and it wasn't until I realized it wasn't working that the power supply was AC. I left my DC one at my moms house and so I grabbed one I had laying around here before realizing what an idiot I am. What parts could this potentially ruin? i had a 30 dollar LCD hooked up? Anyone? I guess I'll find out when I get the DC supply. Thanks all, -Flecko

A professor of mine showed me an LCD he had recently bought from Digikey that is a minimal small 16x2 display. I was impressed with the size of it and asked how much he paid for it, and was shocked when he told me he only paid around $5 dollars(USA) for it. I quickly asked what the part # was for it, and today, he emailed me back and let me know what it was, so I'm passing it on to everyone here to help you out if you're in need of an LCD. http://www.digikey.com/scripts/DkSearch/dksus.dll?PName?Name=67-1781-ND&Site=US Enjoy everyone, -Flecko

Thanks for the quick reply Thorsten, you basically confirmed what I had suspected. Once my 18f452 gets here, hopefully things will progress. -Flecko

I've looked extensively over the schematics for the SID and core modules, but I don't understand how a 40mhz PIC and a 1mhz SID can be connected together without timing conflicts. I ran into this problem early on in my design with my HC11 and SID. The HC11 runs at 2mhz and the SID at 1mhz, so my enable signals sent to the SID weren't latching up correctly. I'm trying to rebuild my design with a PIC 18F452, so my question is, how would I go about interfacing it with the SID? I understand how the serial data/address lines work with the shift registers and all, but the time domain(seperate oscillators and all) part is killing me. Anyone shed any light for me? -Flecko

Having personally used accelerometers, I must say, they're the devil. I'm sure alot of people like them, I just had a bad experience with them. Thats my opinion of course. -Flecko

I can't condone the use of pirated software. Thorsten writes all his code in asm and you don't hear him complaining. I'm going to be purchasing a compiler for my PIC, just as I did with my HC11. Its really best this way, I mean, even if you are on a tight budget, you bought the hardware, why not buy the software as well? If you're not working on something of your own, then you can just use a precompiled version from uCapps and burn it that way, without having to pirate software. I'm not meaning to come down on you, but I'm sure most here will agree this is the right course of action. I will, however, be trying out the demo version of this compiler, just because I'm curious to see how it compares. Thanks again, -Flecko

Ok, that makes perfect sense. Does anyone have any links to any samples of arpeggio? I'll check around on the site and see if I can find any. This sounds like something cool I'd like to implement. Hopefully I can get it right without having to do too much guesswork. Thanks, -Flecko EDIT: Found some examples, this is awesome. I....must...implement!

I know what the meaning of arpeggio is ( http://dictionary.reference.com/search?q=arpeggio .) But I want to know exactly how an arpeggiator works in a synth. I mean, how do you/would you implement one? By rapidly playing the note over and over as the person holds down a key or what? I just wonder if anyone has any further explanation or discussion, as I might want to include an arpeggiator on my synth. Thanks all, -Flecko

After extensive searching, I can say that I haven't found ANY free C compilers for the 18F line of processors. There are a few for the 16F line, but they're not all that great IMO. The only thing I've found that is close to reasonable for a hobbyist such as myself is this: http://www.picant.com/c2c/ If anyone finds anything else, please post it here, this would be nice for those of us that don't like to dig as deep as assembly :P -Flecko

Hey everyone, I felt I just needed to post an update. I got the "new" c64 in the mail the other day(my 4th one if anyone is keeping track) and its SID chip works! My HC11 synth just squeaked its first sound a few seconds ago! I'm totally psyked and really happy. This means I havent' been wasting my time and lots of money. So I guess my design moves forward. Tomorrow, I'm gonna go down to the lab and wire up my 20x4 LCD, rotary encoder, and push button. This thing is gonna be sweet I tell you! I'll be sure to take some pictures and update my webpage. A big thanks to Thorsten and Mindrealm and anyone else who answered my questions ;D There's a good chance I'll have more in the future. Thanks everyone, -Flecko

Yup, I'm an idiot, like I said. Helps alot, thanks everyone ;D -Flecko EDIT: Actually, while we're on the subject, anyone have both .brd and .sch files for a design? That'd help me alot more too! Thanks!

Maybe I'm an idiot, but I'm not finding the schematics downloads on the UCapps? I'd be fine with those, they would be fine for me. If someone can point my stupid self in the right direction with a link maybe? Thanks again! -Flecko

I'm starting to draw my PCB up in Eagle, and I'm not entirely sure what I'm doing. I've mostly used PSpice in the past(also used Magic, but that tool is hell,) so I was wondering if anyone has any of their various PCBs in Eagle format that I can check out? It doesn't matter what the schematic is, I just want to see how it looks. I've cruised around google, and searched the forums, but have had no luck. Its probably right under my nose. If anyone could email me or PM me or whatever, I'd be eternally greatful. -Flecko EDIT: I guess I should be more specific. I want to make a schematic that I can drop my ICs in and solder their legs down, drop in my resistors, and capacitors, solder their legs down, and be done with. Perhaps someone can send me one that they've used in a MidiBox project? Thanks again.

I fixed the menu color, you're right, it looked bad. Although...you could try some of the other styles in the menu ;D The picture is rather blurry that I put on my page, my digital camera just wouldn't cooperate with me for some reason. Hopefully next week, I'll get more parts and get to work some more on it. I was planning on having 3 SIDs total in the end allowing 9 note polyphony. I'll keep everyone posted, and thanks for the comments! -Flecko

hehe, dumb name right? I think so too, but its got its good qualities. That is the name I'm giving my SID synthesizer project. I promised I'd post here when I had some more information available about it, and so here I am. More than just information on the project, I'd like you guys to give me any feedback on my website as well. I've just finished coding it in PHP/CSS using a database approach. Its all dynamic, and lots of nice stats are kept about the whole thing. Anyways.... My site is here. And the FMR64 section is here. Let me know what you think! Thanks, -Flecko

Congratulations mate. I hope to see some pics when you get the time, or possibly some cool tunes to show off your hard work ;D Great job, -Flecko

Thanks again Thorsten. A friend of mine has a working c64 which I'm gonna get over the weekend, so I can at least test my SIDs to see whats up. I think I can say the my circuit is correct, and that maybe the SIDs are at fault, but I'll be able to test it on my own now and figure it out. I've been in touch with MindRealm(he's built a SID synthesizer based on the HC11 too) and I'm pretty sure I've done this correctly. We've been talking about it back and forth and I think its down to the SID chips, I have other homework due soon, so I can't work on my SID stuff till this weekend, but I'm excited now. Thanks again for all the help, and hopefully my next post will tell you about how good it works now ;D -Flecko

Ok, I'm about ready to throw in the towel. I hooked my SID up to a logic analyzer today, and the correct data is getting to the correct spots at the correct times, with the CS and RW signals going low at the right time. I've checked and rechecked the voltages at all the pins on the SID and can see they're where they should be. The output floats around 2V on my R4AR SID, and around 5V on my R3 SID. No matter what commands I send to the R4AR, the output stays the same. On my R3 chip, sending a volume 0x0F causes the output voltage to drop from 5V to around 2V(DC, no oscillations whatsoever). Thats the ONLY command I send that actually does ANYTHING on the output. The louder I set the volume(going from 0x00 to 0x0F) on my R3 SID causes the output voltage of the SID to go a smidge further down from 5V. This is promising to me in the fact that maybe the R3 SID is still alive. On my R4AR SID, changing the volume does nothing to the output, which is pretty disappointing. It should also be noted that my R4AR circuit eats up about 400ma of current while the R3 circuit eats up a measly 200ma(this is including all my HC11 circuitry). The R3 chip doesn't get hot at all either....which leads me to believe the R4AR is broke. I am to the point that I'm willing to mail someone a SID so they can test it and tell me I'm not crazy. I wish I hadn't recieved a broken c64 or else I would test it myself. This is driving me absolutely insane. If anyone can lend me help in any way, please either drop me a message or email me: blf141@psu.edu I'm in dire straights here, I probably wont' be able to sleep now >:( Thanks again everyone, I appreciate all the help. -Flecko EDIT: Also, I am very very greatful to everyone here for listening to and answering my questions. This isn't even really the right place to ask since I'm not building a MIDIbox, but I can't find anywhere else on the net with experts on SID chips. So I thankyou all for tolerating me. I really appreciate all of this.

Ok, I got my 2nd SID chip in the mail...and apparently the C64 it was in is DOA. So I can't test my old SID in the c64, but I tested the new SID in my hc11, and it doesn't work either. But it doesn't get hot either. I'm gonna have to go down to the lab tomorrow and figure out what the hell I'm doing wrong. I'm really starting to get frustrated :-[ Any pointers anyone? -Flecko

Yeah, its fixed. I un-hardwired CS from low to being address matched. And since the SID and the HC11 are now on the same 1mhz clock(no external oscillator) everything is matched up nice. I still have R/W hardwired low, but that shouldn't matter now. I had it hooked up to the oscilloscope earlier today, and it apeared that the address/data/CS signals are all lined up nice. Thats why I'm really stumped this time, because I really believe the information is getting there in the right order, and at the right time. I'm stumped now, downright stumped. Maybe I'll just wait until my commodore64 gets here. Until then I can work on my rotary encodre/LCD menu or whatnot. If you have any more ideas though, I'm all ears. Thanks again, -Flecko

Holding down reset produces a high frequency noise...and then as I release it I get a few audible blips(assumingly everything causing bumps on the power/ground lines as they power up.) So does this mean that its still alive? This is with the output run through a 100ohm resistor, and a 1k pull down, not the transistor. I have a c64 on its way in the mail, and was planning to test swap the chip in it to see if this one is still working. Perhaps if its still alive, I'm doing something else stupid, but at this piont, I feel i've eliminated enough of the variables to remove the guess work. I have to thank you personally Thorsten, you've been very helpful in all this, and when I finish my synth, I will be sure to post some pics. I'm either going to retrofit it in a c64 chasis, or build a handmade exterior, haven't decided yet. Thankyou again, -Flecko