No sound commin out of SiD. any way of testing it easily?

Testing/Troubleshooting
1

Hello!

all should be working ok, interconnection test rated 14/14 so I should be getting somewhere!

I have no Lcd on my 6581 based sid module without control surface so I’m kind of blind as to what is going on in there.

Is there and easy sysex I can send on the fly to get the sid to play a little tune or something?

I have tried MIDIOX keys, but no sound, just an occasionnal high pitched Hiss.

sid chip gets slightly warm too, suppose that is normal?

Thanks for any suggestions!

Alex

2

hi!

Are you shure that the ic´s are the problem?

Do you get any sound from sid if you play a note on your keyboard??

Is the 1.000 MHZ soldered in the right way ?

pwx

3

hi Pwx!

I’m getting closer!

when I power up, after say 3 seconds(probably the time mios takes to boot up) I hear a distant lead tune respond to the keys I play,

but it only lasts half a second and fades away into a big distorted hum.

Maybe my sid is damaged?

I tried wiring the audio cable directly to the sid out pin and it does the same distorted not for half a second, only completely overdriven.

Anyone experienced this before?

My Power supply is 17Vdc@400ma (I dont have the original C64, just the chip) and it supplies the core and sid

at the same time, correctly, at least my meter says so.

Alex

4

Hi mb,

Does it sound like the ‘badsid’ sample I posted here? http://69.56.171.55/~midibox/forum/index.php?topic=4107.0

I suspect it must be SID damaged, as changing it for another SID gives me a working sound.

5

Oups,

your mp3 sounds great if you compare it to mine…  :stuck_out_tongue:

www.gavinaldred.com/poorsid.mp3

thanks for the feedback,

Alex

6

Hi,

17V DC is pretty much, did you also try other PSUs?

Best Regards, Thorsten.

7

Hi!

I also have a 12Vdc 500mA  adapter I usualy use for other midiboxes, but I get similar results with that too.

I’ll look around the house for something else…

best regards,

Alex

8

Ok here’s an update:

I found a 14VDC 800mA adapter but It only makes the sid Roar a sound until it receives a midi note, which stops it dead.

You can listen to a new recording of it here (directly from pin):

www.gavinaldred.com/poorsid.mp3

Anyone heard this kind of sound before fixing something?

I’m allready on the lookout for another chip just in case it’s hopeless.

Anyone selling one cheap in europe?

thanks,

Alex

9

Hi Alex,

this is a really strange behaviour, don’t know if this is really the output of the sound engine, or if a random component like random patch data — which is not the case when the 1k pull-up is connected properly to RA4, or a wrong SCLK line — which is not the case when your hardware *and* software is MIOS V1.7 compatible.

Just to double check:

o are you using MIOS V1.7?

o is your hardware wiring MIOS V1.7 compatible (see http://www.ucapps.de/mios_v1_7_hardware_mods.html

o is the 1k pull-up connected to RA4?

o did you also try out the SID player application?

Best Regards, Thorsten.

10

Thorsten,

Thanks for the advice!

using the sid player, I am really beginning to get somewhere! here is a recording of THE LAST NINJA:

www.gavinaldred.com/poorsid.mp3

It’s another one of those most frustrating moments where things start to take shape in the middle of the night!

the audio line is still wired directly to the SID out pin because I get nothing from the proper pins

I’ll wrorry about that once i know it’s the last step to eternal satisfaction  8)

Does it sound to you like something is still wrong?

I do have last version of MIOS and have checked checked the 1K pullup and the hardware update,

though got myself a bit confused, so here is my core<->sid  hardware config(hope it makes sense):

SID        CORE

SC ------MD (PIN 28)

RC ------RC

SO ------SO

MU ------MU

I just won the bid for a working C64 including PSU, so I’ll keep it in mind as a second chance…

It’s so frustrating not to know what to think of the sound it’s currently producing!!

Hope the new MP3 rings a bell to someone!

I’m off to bed for now because I’m starting to hear my noisy laptop’s ventilator play sid leads   :stuck_out_tongue:

Best regards,

Alex

11

Hi Alex,

this choppering effect doesn’t sound like an error on the SID module, but like a problem with the internal amplifier stage of the SID.

Maybe it makes sense to doublecheck the C1/C2 caps, do you have any short circuit there? If not, then I would tend to test the module with another SID

Best Regards, Thorsten.