Flecko

Well, I'm sure my SID is dead now. I've got everything absolutely working correctly(both HC11 and SID are on the same 1mhz clock) and still nothing. I wrote a program to play a little tune on it, I tried writing the values by hand via the buffalo monitor, and nothing. Also, the chip gets real real hot. I mean, almost too hot to touch. Before I go plunking my other SID down in there, is there anything I should look at? I've got it wired exactly like the MIDIbox SID, except I'm using a 2N3903 NPN transistor on the output instead of a BC547. Should I disconnect the transistor altogether from the output when I test my next chip? I'm only gonna hook it up to an oscilliscope to check and see if the output has anything on it. I mean, to me it seems possible that I've messed up the connections so its somehow drawing too much current. Anyone have any other thoughts or suggestions? I already broke one R4AR SID, lets not let me break another. Thanks all, -Flecko

I'm on it, thanks again Thorsten. -Flecko

I'm using a PAL that triggers the latch on address match using the E clock and R/W signals from the HC11. The PAL i have controls all external glue logic for the HC11, so its working fine. I ended up getting the latches stable by using a few different methods to reduce the noise, and it seems to be latching fine now. Now I'm moving on to my CS problem...I'll figure it out. Thanks for all the help Thorsten. -Flecko

Thanks thorsten. I'm re-evaluating my whole setup, something isn't going right...I need to look at the write timing cycles on the HC11 and the SID. As it is, I have CS and R/W lines on the SID wired to ground, which I don't think works when taking a closer look at the timing diagram. In my mind it should because I always want to be writing to the SID and never need to read it. Mindrealm informed me that he has the SID and the HC11 sharing a 1mhz e clock, which confuses me a bit, but if he got it working, then surely I can figure it out. Thanks again for all the help, -Flecko

Actually yes, its getting its own 1mhz signal. I have a seperate 1mhz oscillator for it, and its been checked and rechecked. I'm not using a PIC in my project at all though. I'm using an HC11, and i have the SID memory mapped in there. I'm waiting ample time for both the data and address to latch up, so thats not it. Is it possible to get a oscope-able output on the SID by hooking it directly up to the scope without any sort of transistor or capacitor in there? I'm getting nothing either way. I ordered another commodore to chop up today, so maybe I can test the chips versus eachother...but I've been over my connections, I'm just not seeing whats going on. Any other suggestions anyone? -Flecko EDIT: additionally, what exact values are people using for caps on the 1st four pins of the SID? I've read a bunch of different values on various sites and even in the 6581 data sheet. Just curious.

Also, given the correct voltages, etc, should the 6581 SID get warm at all to the touch? Mine gets a touch warm...and I don't think thats good. I'm gonna ask this before I plunk a new one down in my circuit. Everything should be working right...this is really bothering me. Any help at ALL is greatly appreciated, Thanks, -Flecko

I hate to say it guys, but I think I may have blown my SID before it squeaked its first sound. I have the address/data latching correctly, so I need to ask a question now. What is the minimal set of writes you must do to make ANY sound come out of the SID? I've tried sending what I think should be the right set up to the SID, and made sure the VOL was turned up, but still nothing is coming out. I've got all my connections right now(oops...put a PNP on the output instead of an NPN ???) so it should be working. I even tried hooking the output directly up to an oscope, and it only hiccups when I write to the SID, otherwise, silence. If anyone can help, I'd appreciate it. Also, in the worst case, where can I get a cheap SID chip(6581 preferrably)? I looked on ebay, but no luck. Thanks again everyone, -Flecko

Ok, thanks. I'll work out a bigger wire guage and some other ideas tomorrow. Thanks for the tips -Flecko EDIT: hehe, thanks

For all the embedded/uC people out there, I need some help. I'm building a synthesizer project using an HC11 uC, and I'm running into a problem. My 74ls373 latch is very sensitive to noise. It latches spurious data if I'm not very very careful with where I hook it up. I'm just developing on a basic breadboard for the time being, but I need some help. My breadboard looks basically like this: http://ece.bd.psu.edu/~cenbd451/lab/pics/P1061675.JPG The only way I can get the latch to work right is to use a high quality motorolla latch, or by connecting my ground/vcc lines directly to the power supply entry point. I've got caps here and there between my ground/hot lines...but it doesn't seem to help. Can anyone help me out here? Thanks! -Flecko