ok… now the problem gets big wiht my sid…
i have two cores both working, (MIOS 1.7 sid 1.6), a usable finished control surface (step B) with LCD,
two sid modules and 7 sid chips… (3 6580 / 4 8581)
the interconnection test works perfectly on both sid modules.
i cannot hear a note from no one of my sids, using either one the other sid pcb.
what other tests can i do???
i have contacted a friend who has a working c64 computer, and i will use it to test my sids, just to be sure.
Just remember that you can test only the 6581s or 8580s on a single C64… :)
Heheh, Mine isnt working either.
Bootstrap worked. I upload MIOS, uploaded the SID_with_CS. I ran the CRC checksum thing for mios, got some numbers back from it…but i have no comparison since I couldnt find the CRC check numbers archive. I have soldered the audio connection both ways just to make sure…nothing. No sound comes out my SID.
All pins registered a 11.98 VDC on the SID Module. I have a SID 6581R4, the last series let out of MOS…but i dont think that should really make a difference.
No LCD at the moment…well I have one, but i think it doesnt function…i plug it in and the IC3 gets very hot to the touch…maybe a short. It sounds like i Know what i am doing…but i dont, heheh.
-Felix
My SID and CORE module connections were not correct, apparently a change in MIOS 1.7 altered the connections. Changed it to the correct way on connecting.
No sound Yet. I am going to resolder the audio connector.
-Felix
resoldered audio connector…no sound…
Edit on my metering:
IC1:Vdd(28 ) and IC1:Vss(14) = 11.910 VDC
all others are 4.978 VDC
Could the 11.91VDC be the root of the problem? Is that voltage to low?
I have replaced the SID chip with a different SID chip (earlier revision).
No sound yet.
???
Bosone,
Look at the connections between the core and the sid module. They are a bit tricky, they are not one to one, look at the C64 PSU schematic and zoom in on the cable connections and make sure you connect it correctly from the core to the sid…i had them backwards and it took me a while to find the error. But now i have a working sid!! ;D
-felix
thanks for the suggsetion…
actually all my voltages are correct, and the sid interconnection test works well, so that i guess that core and sid are connected properly…
now, the problem must be either in the sid or in the output stage… i tried to replace the transistor, but still nothing happens!!! 
i believe im having a similar problem with audio output at the moment, please update the post if you sort yours, i would be interested to see if a solutions for yours would work on mine.
do you get the low level hum on your output or nothing at all?
hi!
when i power on the unit i have a transient in my stereo, to which i connect the sid.
the worse fact is that i “hear” something when i play the notes (or use the sidplayer application), but these are just very low volume electrical transient… these make me feel that something is broken inside the sid, even if i cannot figure why, since i never powered it up with a wrong voltage…
anyway, i still have to test them on a working c64…
that sounds exactly what I have also, extremely frustrating. i know one of my sids worked because i tested it in its donor c64, will post any progress for you! both of my chips are 6581s by the way
all my 6580 sids are good, since i’ve just tested them on a C64… so the problem MUST be somewhere else…
DAMN… it’s so frustrating… even if i’m now happier because i have working sid chips! 
now, let’s take the solder and work on the PCB!
Sorted, mines up and running now, it must have been a bad solder joint somewhere, I checked the lot and re-soldered a few and all is fine ;D
Thanks to all for your input! Hopefully the experiences ive had will be useful for anyone else!
Great Huw!
Matteo: since you have so much SIDs, it’s worth a try to connect the audio input of your stereo directly to the audio out of the SID chip. Although this can be dangerous (on the other hand: it never caused problems with my SIDs), it gives you the important input if the transistor stage is really the problem, or if it is located anywhere else..
Best Regards, Thorsten.
my sid and pcbs are working now , and i’ve found the problem
i’m using mios 1.7, sid 1.6, with working control surface and bankstick, so i assume all the mods and cablings are correct
the sid modules were not running because of the clock!!!
previously (including the days when all my setup was functional), the sid clock line (res, pin5) was connected to core J14 PIN.
then, suddenly, one day the sid stopped working, and i cannot figure out why…
until now, when i mounted a 1MHz quartz on the sid module, and disconneceted the J14 core cable!!!
before adressing this… i checked ALL the connections, the sid interconnecting test was OK, and i even check the correct connection (with the tester) between PIC pin RD4 and SID pin RES# (directly between the two ICs)
i have two core+2 sid, and only one 1Mhz quartz crystal. so i decided to connect the second sid module directly to the quartz out of the first pin it works, even if the signal is very bad, and the sound i get is not at all “clear”. probably because the clock signal gets deteriorated during the travel…
the funny and incredible thing is that if i desolder the cable from the quartz and i connect it again to the J14 pin of the core, it doesnt work!!!
i cannot believe is a PIC problem, since this would be the only output broken… is this possible??
J14 is not the right pin, from the MBHP_SID page:
The SID has to be clocked at 1 MHz. As clock source either an integrated 1 MHz crystal oscillator, or the middle pin of port Core:J7 (PIC Pin #17, which is configured as 1MHz PWM output with 1:1 duty cycle) is supported. The results are the same - take an oscillator if you are able to get one for less than 3 EUR, or wire the SID clock input (Pin #6) directly to the PIC PWM output
so, if sharing the clock from a single crystal doesn’t work, why not using the PIC clock output of PIC Pin #17?
Best Regards, Thorsten.
this sounds rather new to me, because i’m absolutely sure that, in the past i always used the J14 PIN… ???
anyway… perhaps i miss something, probably because of the LONG hours spent on soldering!!
anyway, i thank you for this… i thought i have read carefully all the ucapps pages, but evidently this was not true…
i’ll try as soon as i’m at home!
One of the joints I had to resolder was the oscillator output on the SID board, I wonder if this was why we were both experiencing similar symptoms, glad to hear your boards are all going fine now ;D
now my SID unit is working!
i need only to make all the proper connections in a convenient way and place all inside the case!! ;D