AndrewMartens

I just thought that I would bring your attention to the PIC Polywhatsit, initially designed by EPE Magazine in December 2001 - http://www.epemag.wimborne.co.uk/projects2001.html It's a PIC-based 8-bit effects unit that does echo, reverb, delay, flange, phasing, vibrato, and a crude pitch shift up/down. I have a PDF of the article here, and ordered a set of PCBs from them (along with a copy of that backissue). It sounds like it will be a crude-but-usable device - just the sound I'm looking for. I'm hoping to eventually adapt the design to run under MIOS, possibly even using the Core board (their design uses almost all of the 33 I/O lines on the 16F877). After all, the 18F452 gives us a lot more processing power than the 16F877 (which is what they used in their design). As to how well it works, I'll post the PDF and some sound samples once I've received the board and put it together. If it's junk, I won't bother MIOS-ifying it. If it turns out to be "good enough", then you can bet I'll try to put together some code that will run under MIOS. Assuming, of course, that I can finish my Midibox SID, design & build a Midibox PSG (using the YM2149F and AY-3-891x). Then after this I'm thinking about a crude 4-bit sampler, and possibly a synth engine that runs on a PIC...

Excellent, I was just looking for one of these the other day - going to make a basic MIDI merge + driver in one box.

WARNING: I haven't made a Midibox64, have only looked briefly at the layout and at the IR sensor. It should be possible to hook the output of the Sharp GP2D12 sensor to one of the 64 analog inputs. From what I've read, the output is roughly between 0.4V and 2.45V. You would probably need to do some scaling for your device inside of MIOS before transmitting it via MIDI - otherwise you will probably only transmit MIDI values from 10 to 62 or so (again, I'm not sure, just guessing here).

Hi, I did a few searches and didn't see an answer to this anywhere - hopefully I'm not just blind or stupid. Plan: Anyways, I have two joysticks (picked them up surplus a year ago for $1 each, I think they're the same as used in the Red Sound Darkstar) that I plan to connect up to a dual-SID CS B. Ideally I would like to hook up one joystick to each Core module, and have it only control the filter on each SID. Dual joysticks for dual filter fun, yay! Question: If I use a 16F877 (I have a few sitting around) as the slave Core module for this dual-SID unit, can I connect one joystick to the master and one to the slave? Or is it necessary to wire both into the master unit and then configure MIOS to transmit Midi CC's for the second joystick? Hopefully I'll finish all my wiring, testing, and get this mounted in a case within two weeks - then I can move onto my other MIOS-based chip synth designs (as mentioned elsewhere)...

I won't make any comments about Google here, but I believe someone posted this URL earlier: http://members.chello.nl/h.otten/vortexion.htm It has a link to the YM3812 datasheet, which can be accessed directly here: http://www.funet.fi/pub/msx/mirrors/msx2.com/vortexion/ym3812.pdf Regarding OPL2 vs. OPL3, I think that the YMF262 was the first chip supporting OPL3 (and was also backwards-compatible to OPL2). Still, the YM3812 might make a cool project - maybe TK will get to that after his YMF262 FM synth ;-)

I was pleased with the resistor spacing on the Core R3 board, as I mentioned in a previous post - it works quite well for 1/4 W resistors (at least it does for me). Â However, I found that the SID R2 board seemed designed for 1/8 W resistors - I just bit the bullet and ended up with my four resistors sticking out like little launch ramps. Â Not that it matters with that monster 2200 uF cap there :) Â In general, it might be nice to have sufficient room for those on the SID board as well, IMO. On a side note, for one or two of the side J-connectors on the Core module (and I believe for one on the SID), I found that there was not enough room to mount a nice latching plug due to a resistor or capacitor laid out too close. Â Not a huge issue - I just used a SIL header instead - but perhaps something that could be considered for a future revision. Â I'll post the connector number when I get home later today. Still, the boards are fantastic and putting them together is a breeze. Â If I hadn't ordered the wrong trimpots from Digikey (again, I really should have bought those kits!), I would be up and running already... UPDATE: the connectors that could use a bit more spacing are J3 and J4 on the SID (C5 and C6 are a bit too close), and J13 on the CORE (R11 is a bit too close).

When I started wiring up my newly-arrived Core & SID modules last night, I remembered that a few years back I had pulled the old soundcard out of my 486 (when I started using it as a router). After finding it in a drawer full of parts, guess what I found? That's right, a YMF262! The one old soundcard that I have, and it's got the right chip on there. Hooray! The card is a "Mediamagic ISP-16", for those who are looking for old ISA soundcards to loot.

I dug through my parts box last night and found almost everything I needed to put together one Core module. Â I'm not quite sure of your technique, but here's what I used: - hold the resistor body with one hand - pressing with your other hand's thumb starting on the resistor body and rolling over the end of the resistor on one of the legs - repeat for the other leg About 90% of the time it gets it close enough to the resistor in order to have a nice drop-in fit into the PCB. Â 5% requires a press fit, and the other 5% I have sitting at about a 10 degree angle up from the board because I was too lazy to re-bend the resistor. These boards are great! Â It only took me two hours to wire up a Core module, and about 90 minutes of that was digging through all my old parts to see what I had available :) Time to order up some 2200 uF caps (I _knew_ I forgot something!) and a case to drop this into. Â Oh boy! Regarding "being rough" with resistors - well, they're tiny passive devices that cost pennies... may as well be rough with them. People shouldn't be afraid of damaging the resistors - just order a few spares!

My boards just arrived in the mail yesterday, and I picked them up this morning. They look great! I may be working 12 hour days, but hopefully today I can go home and get most of a Core and SID module wired up tonight. With any luck, I'll have a nice dual-SID box up and running within two weeks, and I'll be able to move on to my YM2149F synth. I'm kicking myself for not ordering the full core & SID kits, though. "I'm not paying $10 USD for stuff I may or may not have in my parts box... instead I'll spend hours digging through it and tracking down all the part numbers that I don't have!" Yeah, that was a GREAT idea by me :P

Wow, you work fast! I haven't even received my MBHP boards yet - first I have to build my SID, then I have to get going on my other chip synths. Unfortunately, it's Saturday and I'm at work AGAIN... things aren't boding well for this at the moment, but with any luck I'll have a new job in 3 weeks which should give me a bit of free time. You never cease to amaze, TK :) I'm looking forward to when a PCB is ready for this (though really, it seems simple enough to wire up on some stripboard)!

I've got a pretty good set of datasheets for the new chips that I ordered. Mostly what I need to figure out is how those demo coders did what they did with the chip - so far it appears to be wavetable / arpeggiated chord stuff which has been implemented for the SID already. I think it was on the Atari ST where they took advantage of a 50 Hz interrupt to modify the parameters of the YM2149 - once I have basic sound working, I'll probably start in on that angle. Maybe faster modulation, though - hadn't TK said somewhere that we can modify at 1120 Hz? Just a wee smidge faster than 50 Hz :)

Ahh, excellent! I'll have to look around and see if I can find any of those somewhere. I've been meaning to experiment with FM synthesis but never found a convenient source of ICs to use. Maybe I'll have to dig up some old ISA soundcards from somewhere... I'll have to see if I can get my "MidiBox YM2149" working before your Midibox FM ;) Not sure where you find the time to work on all this, though!

The AY-3-8914 is from the Intellivision, and the YM2149F is from the Atari ST. POKEY chips were found in a number of Ataris (5200 and 7800 consoles and the 400 and 800 computers, I think). I looked at the Midibox SID code last night: most of it should be re-usable, at least to make a basic working system with these chips. I don't have any experience writing demo music / chiptunes, so I don't really know what features musicians will need in the software in order to create cool patches. That's getting ahead of myself, though. Once my MBHP boards get shipped from SmashTV (after they're back in stock, of course), then I'll focus on this a bit more. I'm going to steal the MBHP interface and output amplifier circuit from the SID module, and that should really take care of the hardware side of things.

Hi there, I'm Andrew Martens, the guy who worked on the SIDgroove project (referenced by TK on his Midibox SID project). Ironically I never finished it, and I'm going to be ordering some MBHP_CORE and _SID boards so that I'll finally have a working SID synth. :) Anyways, that's besides the point. The other day I ordered a few other old synth chips: an AY-3-8914 (compatible with the AY-3-8910 and -8912), a YM2149F (pin compatible with the above, but apparently the registers are swapped around), and a pair of Atari POKEY ICs. At first glance, it appears that I should be able to leverage the core module and MIOS in order to start off with a working hardware & software platform to make an add-on board for. Is there anyone out here who might be interested in something like this? Please note that if I do get around to making this work, I will definitely provide TK with schematics and code for this so that he can develop something better with it. ;D I'm not sure if I'll start on the 891x board or the POKEY board first, but I'll keep you posted.