th0mas

From http://www.ucapps.de/mbhp_ain.html: All unused analog inputs have to be clamped to ground (Vss), otherwise your MIDIbox will send out a lot of random MIDI events!

(this deserves a double post :) ) It works! I used an NPN transistor from some random board I had to connect the 'record' input pad and ground. Time to wire up a couple :D

datasheet for the microcontroller used: http://magnachip.com/download/GMS97CL2051_1051_Manual.pdf Conceptual question: Instead of using transistor relays attached to the contacts for each switch (play/record), could I instead just: - reclaim a bunch of pins that are unused on my CORE PIC (IE, pretty much all of them, since I'm not using an LCD or anything else.. maybe a DIN if it's needed at most) - tie the GNDs together for the CORE and the audio sampler (already will be; same power supply delivering 5v) - connect PIC output pin to the sampler's microcontroller input pin edit: update (to avoid double posting ;) ) I have a dedicated core running MIOS v1.9 and a small application that raises PortB (all pins) on note on, and turns them off on note off. I have one wire coming off of port B (D7). Now, to get it to trigger the sampler and we're in business! :D side note: I can't believe how freaking easy this is. Seriously, between MIOS, surrounding applications, and the C function wrapper, and the quality boards I got from SmashTV, I am in the community's debt! Thanks all!

Wahoo the store's open!! :D Just in time, too.. I just finished my SID with a control surface A, tested it (it works!), and tried to tighten up my mounted encoder with some superglue.. let's just say now I need a new one (and more) ;).

Here's my conceptual schematic: http://th0mas.sixbit.org/mbsampler-1.png In reality I'd like to think this schematic would be a general purpose MIOS->relay circuit, pretty much based on how the SID module goes from serial->parallel access, then to transistor relays on the pads of the play/record switch for each recorder (only 1 shown in the schematic). Any flaws? If flaws are major just say "there are major flaws" and I will go re-learn basic electronic knowledge I'm probably forgetting, or never really learned ;) edit: note that I forgot OE#->GND on both of the ICs.

If only I could determine nanoseconds with my eyes/ears ;) Basically, I tried humming a constant tone, and pressing record, waiting a second, pressing record again to stop the tone. When I hit play, the tone starts without apparent delay - feels about the same as pressing a trigger on a real sampler would, and faster than most virtual samplers I've played with. Some characteristics of the device aren't the greatest for a sampler: - the sound apparently has to stop before it can be retriggered, you can't go "Yo-Yo-y-y-y-Yo" for example. I might be wrong, and it might actually just operate such that hitting play while the sample is playing stops the sample. There might also be some glitchy way to accomplish this that I haven't found tinkering yet. - no sample editing capabilities, period. - while you can store multiple sounds on each device, the only interface to swtich sounds are "previous sound / next sound" which makes for a weird MIDI implementation to select patches. - most often recording has a 'click' right at the start, which would suck. A simple noise gate might minimize this but then it'd probably mess up the recording sound's envelope. Wouldn't be too bad if we're dealing with recorded loops instead of one-shots. As of now I have not looked up the datasheet for the controller, I've only been playing with ideas of connecting the already existing switches to transistor relays to two 74HC595's to connect to J10 of a core module. Seems they only take up ~10 mA current when either recording or playing. Needs a battery in order to save patches. I'm interested in turning this into a lo-fi weirdo instrument, so I hope to be able to 'bend' the circuit a bit, maybe be able to modify pitch/timing on the fly with a potentiometer, stuff like that. There's no crystal that I see so maybe timing's determined with a resistor/capacitor combination, which I could bend pretty easily. That is, if I remember any electronics, and I probably don't ;), so I don't really know. In terms of MIDI implementation, I'm expecting it to just respond to specific note events on a midi channel and trigger the corresponding device. I'll try to post pictures in the next couple days, along with the start of an infinite number of questions ;).

I bought my chip from him, I think it's my fault his prices are higher actually. He was selling 4 for 80 (iirc) and I told him I'd buy one for $25 (I had been looking all over for ~2 months with no luck), ever since then his price has been higher. :-X

Latency is very low, and device doesn't seem to mind being fed 5v instead of 3v from batteries ;) more/pics to come.. Could a moderator move this to maybe "Design ideas" or somewhere else similiar? I'm now in the process of turning these devices into a DIY sampler and am going to have a series of questions. cheers, Tom

I did something similiar - I accidentally had my two polysterine caps shorted against each other (the two closest pins on the R3 SID PCB). One question - Should I now replace those caps? When they were shorting I was getting very very odd sid behaviour - the synth was essentially busted. Unshorting them, I now only have an issue with the filter - it quiets my input down nothing whenever I use it. Can I test the caps with a multimeter? Cheers, Tom

As the title says. I just bought 6 of them, wanted to bring it to any interested party's attention: http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&item=5799268272&ssPageName=ADME:B:EOIBSA:CA:11

If anyone wants to get rid of their semi-broken 6581's, I can take them off your hands (ie, if you're never going to use them, and would be happy knowing someone would). Frankly I'm enjoying my half-broken SID synth and am considering building another (plus I'd like another semi-broken SID as a backup in case mine eventually kills itself from the pain) Cheers, Tom

No, but that's what I figured. I like it, so I don't think I'll bother with a new SID unless one falls into my hands for cheap :)

Sure, I can do that, I'll poke around for the best place to do so. Edit: Actually, I should investigate it's usage a bit more first, see if anyone has any suggestions and make sure it _is_ an appropriate power supply. My 6581 SID operates pretty weird. It often does things such as, OSC's randomly drop out of notes, filtering seems to be very inaccurate (doesn't really do what it should in any mode, sometimes it does but doesn't always), etc. OSC's sometimes play the wrong frequency (and hitting the note a second time, the OSC will play the right frequency). Basically every time I play a note there's a certain percentage of the sound that is random. If I apply the filter to all the oscillators, then often the sound simply cuts itself off. Does this sound like problems induced by a bad power supply? (keeping in mind that I *did* potentially roll over my SID chip with a chair, so I could just have a half-busted SID at this point ;) ) FWIW, I love it anyways, it's unpredictable-ness makes for a far more entertaining synth than anything I could buy. Cheers, Tom

Well, it appears not to be a problem, because MY SID WORKS!@#!@#! :) Thanks a lot for the replies. Now for something to make your blood run cold: Yesterday, when I was soldering my SID module, I took my SID chip out of it's case to check the version and ensure that it is a 6581. Being in an uberfocus, I then placed it on the desk and continued working on the SID module until it was done (including posting the messages from above). This morning, I find my SID chip face down under the chair next to my desk, pin's bent all over the place. I think I rolled over it with my chair. :o Yet this is the SID that is powering my synth, so all's well that ends well I suppose :)

I just measured my voltages, and.. the SID module is being given 12v. I have a 12v regulator stuffed on the board currently. Pin 14 to Pin 28 of the IC1 socket, however, is only 9V! Do I have to short out the regulator? Edit: shorted out the regulator, now I get 11.78V. Cheers, (and thanks everyone for their help!!!) Tom EDIT::: IT WORKS!!)#($!@)(#!@#K!M@#L@!K#M YAAAHOOOOO!!!

Sweet! Thanks for the reply, I'm about to try it out! :)

I also have one of these powersupplies, and I just realized it after already building the optimized power circuit for the standard C64 power supply :( (not a big deal, anyways..) Can I just plug this right in? the Pinout is +5v/+12v/GND (other pin is NC). I'm using a 6581 and currently my SID board has a 12v regulator in it, which I'm assuming would end up doing nothing (but is it okay to leave it there?) The reason I ask is that someone said: "Of course, a new optimized power circuit would have to be designed, but how about it?" Is this necessary? Cheers, Tom Edit: The readings from the PSU are giving me: 12.08 for the 12v DC, 5.58 for the 5v DC. Is 5.58 too hot?

nope, more like white plastic-y. I'm just about done my power supply, so I'll let ya'll know if I'm getting the right voltages or not. Thanks for the reassuring words regarding the durability of the caps, makes me feel a bit safer :) Cheers, Tom

Thanks for the quick reply!! regarding the ceramic cap, if I don't get the expected voltages I'll post pictures, otherwise I'll assume it's okay - I'm pretty sure it's just a bit of heat stress.

Hi, First of all, thanks everyone for an awesome project, and thanks SmashTV for an awesome service - I love the boards!!! Onto my question: I've noticed that: -I only have 1 capacitor marked 102 - the parts list on SmashTV's website does not include anything identified for C7 Am I to assume the one 102 capacitor is for C3 and leave C7 empty? (despite there being a C7 capacitor in the board livemap on Smash's website) Also.. how bad is it when a ceramic cap starts to well, seemingly give off a translucent plastic? Is it fried? It happened a bit on my core module, and the module appears to work fine (voltages test fine, etc). Cheers, Tom

Are you sure it doesn't work with linux? I have one and it appears to work fine - you have to use (iirc) fxload to load the firmware driver in your usb hotplug scripts. but to be honest I don't think I ever actually plugged in an external peice of gear to see if notes were being sent or not, so I could be sitting on an unusable device as well :)

Posting the link because I actually just picked up a board with the chips on it. This seller wrote back to me that the chips are on the board, but I already bought the other one so I figure I should let people know. The board is a "Gateway / Creative CT2890 ISA Sound Card", so I guess if anyone can verify the seller's claims then it should be added to the database. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5149530519&sspagename=ADME:B:AAQ:US:1 Cheers, Tom

I'm planning on having any changes made on the fly not be saved to the patch, like the way the korg electribes work. To save you have to be stopped and press "save". Saves writing issues on the fly. Thanks for the reply, I'll kick some ideas around in my head. Cheers, Tom

cool, no rush, whenever you get to do it :).

Hi all, First off.. thank you everyone involved in creating this project (obviously especially TK). It appears to be quite nice and easy to work with. I'm writing a x0x style sequencer (yes I've seen the other threads, but I want to do it myself :) ) from the clockbox example and have a couple questions, as I have not ever written PIC code before. I've been mostly programming for efficiency with regards to size: for example, in a "pattern" struct, I need 4 bits to store which midi channel each part plays on, so I've been storing 2 midi channels in each byte and using only 4 bytes instead of 8 (for each of the 8 parts), then I just extract them as needed using '>>4' or '& 0x0f'. Is this overkill? Also, my pattern struct is 320 bytes (5 pages). Can I read 320 bytes from the bankstick on the fly without jittering timing? If so, how? (I haven't tried just plainly 'doing' it, as I haven't received my modules yet and am just coding without testing :) ). Cheers, Tom