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Midibox SID v1 dead chip?


yatagarasu
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I'm going through a bit of debug hell.

- I put together a Midibox core module (ordered from Smash TV, BSL 1.2B, MIOS 1.9).

- I assembled the SID module using the 6581 from my youth.

- I put a 9V battery to the J1 of the core and a 15v wallwart to the J1 of the SID (just to be sure there's enough power to go around). The CORE gave the proper bootup hex message upon connection.

- I connected the modules and got no proper sound from the audio (very low ambient noise).

- I uploaded the interconnection test sysex and got the correct Voltage readings (5V from all but CS# when mod wheel events are sent to them).

- Still, I get no SID notes.

Here's a weird twist. I unplugged the "MIDI IN" jack on the core and plugged into the "MIDI OUT" so that I was sending data to the "MIDI OUT" jack. When I send note data, I get toneless clicking sounds in the rhythm of my playing. Also, when I upload sysex, a weird 8-bit noise swoosh is heard. Cool, but useless. I thought it would help troubleshooting to include it.

Is it my chip? Do I need to just spring for a new one? This is getting to be agony but it will all be worth it if I can just hear a rezzy 303 buzzline off of my dear 6581!

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LOL NLX... look at the topic  ;D

yatagarasu: That midi plug thing sounds like you have a short somewhere...

Have you tested all the voltages?

Uploaded mios and the application using smart mode in mios studio?

What PIC?

You mentioned the interconnection test... which one?

Lots more information please :)

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Yeah, screw sleep! :D I certainly appreciate your attention and replies!

Here's more info, per Stryd_One's qs:

PIC is 18F452.

I haven't tested all the voltages. I  wasn't sure if I needed to, since the interconnection test passed. The test I ran is: mbsid_interconnection_test_b. 

But if I was to check all voltages, I would check the schematic for how much V is between each component, right?

I have not uploaded mios using smart mode in mios studio. I thought since I bought a pre-burned 18F452 from Smash TV the chip was good to receive and transmit midi and drive the SID. An oversight on my part? 

I haven't tested the chip in a commodore. I just ripped it out of my old c128 (a 6581 in a 128!), and I don't have the monitor so testing might be a pain. But I'll see if I can boot it up next opportunity I have (I might have ruined it pulling the chip D:) . But what's weird is that I deffinitely get 8-bit noise when I send data to the MIDI OUT of my mb. So could it be that PART of the chip is messed up? Or is the Core or other components that make those sounds? Is there another way I can test the chip besides finding a working commodore?

Anyway thanks again for your help. This is my first MidiBox (well, second counting my first botched SID unit :D) and I'm still getting the hang of board work. 

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Sorry this one took so long!

I haven't tested all the voltages. I  wasn't sure if I needed to, since the interconnection test passed.

You definitely should remove your SID and test all the voltages... I'm a bit worried because I'm sure the instructions on ucapps.do say to check this first, so maybe you aren't following those instructions... You should :)

But if I was to check all voltages, I would check the schematic for how much V is between each component, right?

See the above.. There are tests for certain voltages on certain pins.

I have not uploaded mios using smart mode in mios studio. I thought since I bought a pre-burned 18F452 from Smash TV the chip was good to receive and transmit midi and drive the SID. An oversight on my part? 

Yeh... Smash's PICs come with the bootloader, and recently also MIOS, but not the MBSID application. If you haven't uploaded the application it definitely won't work!

But what's weird is that I deffinitely get 8-bit noise when I send data to the MIDI OUT of my mb. So could it be that PART of the chip is messed up? Or is the Core or other components that make those sounds? Is there another way I can test the chip besides finding a working commodore?

Well that could be one of many things. At this stage, I would disconnect the SID module, test all voltages, get the core working correctly, connect the SID module and test it's voltages, insert the SID and then test.

Let us know how you go :)

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Quote from: yatagarasu on 2007-10-12 at 22:28

I have not uploaded mios using smart mode in mios studio. I thought since I bought a pre-burned 18F452 from Smash TV the chip was good to receive and transmit midi and drive the SID. An oversight on my part?

Yeh... Smash's PICs come with the bootloader, and recently also MIOS, but not the MBSID application. If you haven't uploaded the application it definitely won't work!

Blah..hugest oversight ever..I'm sure I knew this at one point but my brain is half sequencer at this point :D

Thanks for yr patient advice, I'll try everything in order tomorrow and keep you posted with the results.

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Ok, I uploaded firmware and bingo! SID sounds! I am rocking the square wave and recording new tracks with the subsequent burst of inspiration. Thanks for your help guys!

Now to build the enclosure and optimize the power source (with a c128 psu, but that's for another thread I suppose!).

MB MB MB!!!

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