PROPHET64 & MSSIAH Userforum

8bitapocalypse · 2006-07-12 02:55:51

i have an old style c64 with 6581 sid chip.
the sequencer works fine, monosynth works fine, drummer as well.
BUT i cant seem to get a proper sound out of the bassline, i program a sequence and run it - all i hear is the rhythm of the sequence tapping away at a really low level. the knob controls dont have any effect on the sound at all.
i think i read somewhere that the bassline is optimised for 8580 sid chips, does that mean it doesn't work properly on 6581 machines??

anyone else having this problem??

Slorrin · 2006-07-12 02:59:28

someone else in the yahoo list had the same problem.. maybe it was you though..

8bitapocalypse · 2006-07-12 03:01:34

haha yes it was probably me!! i cant work it out, im not too bothered as the monosynth is similar, but its a shame if it doesn't work properly.

8bitapocalypse · 2006-07-14 19:01:56

so, am i the only person trying to run bassline with a 6581??
can anyone at least verify that they have a 6581 machine running bassline properly (or not as the case may be)?

KONEY · 2006-07-14 19:45:17

My bassline on the 6581 sounds ok. The only this is that I don't plan (for now) to employ it.

8bitapocalypse · 2006-07-14 19:50:41

thanks koney, do you know what specific 6581 you have in your c64?

KONEY · 2006-07-14 19:56:08

I dont know...can you tell from this picture?

http://img175.imageshack.us/my.php?imag … ted4oa.jpg

Next time I open the case I will write down revision of 6581s

8bitapocalypse · 2006-07-14 20:11:53

cheers koney, im just trying to narrow down what could be the cause of the bassline not working on my machine.

looks like you have 2 rev 3 chips from 1984 maybe??

i have one from 1982 and it must be rev 1 or 2. could be the problem?

KONEY · 2006-07-14 20:14:25

theorically EVERY revision should work fine...

Try by exchanging the chip with another one....

Last edited by KONEY (2006-07-14 20:15:32)

Jaicen · 2006-07-14 21:38:49

Certainly looks like a Rev2 SID, afaik they don't have any rev markings on them at all. Do bear in mind that some of the SID's, especially early ones don't work properly, particularly with regards to the filter. Do you find that the MONO synth works when you don't assign the filter?

8bitapocalypse · 2006-07-14 21:50:17

i have just tried and the mono synth DOESN"T work when i switch the filter off!

KONEY · 2006-07-14 23:30:35

AHH today I switched the commodore on and the P64 says REVISION 8580! AHHHH.

ON/OFF and it was 6581 again...

FUnny....

Jaicen · 2006-07-14 23:50:42

It's normal for that to happen with the filters. Just set it wide open with no envelope.
According to the p64 website, one in six times the cart will incorrectly detect the SID version, so that's to be expected.

Slorrin · 2006-07-15 07:22:07

the 6581/8580 is not perfect.. if i create a PSID prg in the menu, when it's done it says i have 6581, even though i have 8580.

that's life

8bitapocalypse · 2006-07-26 14:24:25

i have just replaced my old 1982 sid chip with one from 1984 and STILL the bassline doesn't work!! WTF??

8bitapocalypse · 2006-07-26 19:35:34

well i bought an entire board on its own, so i have all the other chips spare as well, if i knew which chip might be faulty i could possibly replace it?

i guess it may not be the sid chip anyway, at least i have a spare one now!!

Jaicen · 2006-07-26 19:57:13

Amigatrash, what symptoms does your C64 have?? When you turn it on, does it occasionally start up with a garbage screen?? How much RAM FREE do you have on startup?? Also, have you tried running your SID with the old free versions of TB and MONO? If they work it could be a software issue.
8bitapocalypse, I don't suppose you could supply me with the two 74SL257 chips off your spares board (assuming it's the early large breadbin board). The ones on my board appear to be damaged and I'm having trouble finding any in the UK.
Do you know what's wrong with your board?

8bitapocalypse · 2006-07-26 23:58:24

Jaicen wrote:
8bitapocalypse, I don't suppose you could supply me with the two 74SL257 chips off your spares board (assuming it's the early large breadbin board). The ones on my board appear to be damaged and I'm having trouble finding any in the UK.
Do you know what's wrong with your board?

well, i was thinking of keeping the board for spares for myself, but i would consider swapping the two chips for a working 8580! : )

i have absolutely no idea what is wrong (if anything) with my board (hence the thread), all i know is the bassline software does not work with the 2 chips i have tried.

Jaicen · 2006-07-27 00:46:31

Hmmm, 8580 = £10-20, 74SL257 = £0.80
Is it me or does something not add up I think i'll pass thanks!!
If you've tried two different chips in the same machine, then it's likely that it's the machine causing a fault in the addressing of the SID's. Like I said before, i'd run a copy of the old MONO and TB versions and see if they behave in the same manner. If so, you can be reasonably sure that it's a hardware issue.

PROPHET64 & MSSIAH Userforum

#1 2006-07-12 02:55:51

bassline NOT working properly with 6581 c64...

#2 2006-07-12 02:59:28

Re: bassline NOT working properly with 6581 c64...

#3 2006-07-12 03:01:34

Re: bassline NOT working properly with 6581 c64...

#4 2006-07-14 19:01:56

Re: bassline NOT working properly with 6581 c64...

#5 2006-07-14 19:45:17

Re: bassline NOT working properly with 6581 c64...

#6 2006-07-14 19:50:41

Re: bassline NOT working properly with 6581 c64...

#7 2006-07-14 19:56:08

Re: bassline NOT working properly with 6581 c64...

#8 2006-07-14 20:11:53

Re: bassline NOT working properly with 6581 c64...

#9 2006-07-14 20:14:25

Re: bassline NOT working properly with 6581 c64...

#10 2006-07-14 21:38:49

Re: bassline NOT working properly with 6581 c64...

#11 2006-07-14 21:50:17

Re: bassline NOT working properly with 6581 c64...

#12 2006-07-14 23:30:35

Re: bassline NOT working properly with 6581 c64...

#13 2006-07-14 23:50:42

Re: bassline NOT working properly with 6581 c64...

#14 2006-07-15 07:22:07

Re: bassline NOT working properly with 6581 c64...

#15 2006-07-26 14:24:25

Re: bassline NOT working properly with 6581 c64...

#16 2006-07-26 19:35:34

Re: bassline NOT working properly with 6581 c64...

#17 2006-07-26 19:57:13

Re: bassline NOT working properly with 6581 c64...

#18 2006-07-26 23:58:24

Re: bassline NOT working properly with 6581 c64...

Jaicen wrote:

#19 2006-07-27 00:46:31

Re: bassline NOT working properly with 6581 c64...

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