163 replies to this topic

[frailn]

I do not know if the chip I will receive is still working.

That brings up the topic of me testing the chips from Kevin if I run a mini-sale. I'll have to build the midibox first in order to do that. Unless someone has a better idea for testing these...

EDIT:

I suppose I could buy a ZX Spectrum for testing purposes. Looks like the mother board is set up with a DIP socket, so I could plug in the chips and test each one.

Nevermind - upon closer inspection, the sound chip is soldered to the board.

[mrcam]

EDIT:

I suppose I could buy a ZX Spectrum for testing purposes. Looks like the mother board is set up with a DIP socket, so I could plug in the chips and test each one.

Unfortunately your picture is from a classic zx spectrum without any soundchip and not from the 128 version with the ay-3-8912... but it is still soldered!
you can see that chip on: http://mpc.fab.free....air/pzxvszx.htm

[frailn]

I've been researching some other platforms that used this sound chip. The old Vectrex video game systems had the AY-3-8912 in an IC Socket, according to the tech manual - NO DESOLDERING. Ideally, getting my hands on a Vectrex and the test cartridge would work. The test cartridge plays a sound through each of the three channels, starting at a low frequency and going up to a high frequency. However, if I can just get a Vectrex, perhaps there is a video game that will run through all three channels. Finding the test cartridge would be hard to do.

If anyone has knowledge of an available test cartridge for the Vectrex, let me know!

I'm eyeballing some Vectrex auctions on eBay. It would be cool to own one to play with, in addition to using it to test sound chips.

[buhler]

Is there enough interest for me to start a Mini-Sale? Anyone? Anyone? Buhler? Buhler? Anyone? If you guys are interested, I'll need to slap up a wiki page.

why do you tempt me so frailin?!?!  i already have one AY38912... and an ungodly amount of SID's, POKEY's and all the OPL chips...  i sort of have the fear i may not be able to get the IC's sometime in the future. :  anyhow, with that logic... i guess i could go for another! ;D

[frailn]

LOL! YOU MUST BY MORE CHIPS. MANY YEAR TO COME FOR PROJECT.

I just got a response from Kevin.

I received a reply from the last supplier I was waiting on. I am able to get more N.O.S. parts and offer the same pricing that is listed on my website. I can't offer any further discount, but you can buy as many as you want (50pcs, 100pcs, 200pcs, etc) for $3.99 each. Therefore, please let me know if you would like the 50pcs right now, or if you would like to wait for aproximately 2-3 weeks for me to receive additional quantities, and then send everything together.

So! the price is a little higher than originally quoted, but on quantities, the sky's the limit. At $3.99 each + $.42 PayPal fees, the cost per chip would be $4.41 USD or 2.94 Euro or 2.30 GBP or 4.95 AUD. Not sure on shipping, I need to study Wilba's shipping methods to make sure I keep that cost low. I'll cover the cost of the padded envelopes, I can get them cheap at the wholesale market (or five finger discount at the office).

I'll set up a MINI-SALE WIKI page tonight or tomorrow to see how much interest we have! I know there's a bunch of midiboxers with C64 keyboards laying around just waiting to hook up to a Lemonhorse AY-3-8912 Synth!

[buhler]

well... count me in!   although, i may buy a few SN76477's from Kevin...  i'll just do that separately.

[lemonhorse]

hey hey!!! 

[mrcam]

There is no reference to the turbo-sound project: http://velesoft.spec...rbosound-cz.htm
The goal is not similar (improving sounds in a zx spectrum)... but the schematics are interesting.

edit: turbo-sound example (warning: lot of noisy waves)

[jimh54]

mrcam,
It does indeed look interesting, but the site and documentation needs translation for us monolingual types. The Data sheet for the YM2149 shows it to be pin compatible with the AY3-8910/12. It may do the same thing.

[mrcam]

I tried to find some czech <-> english online translator but it was not very usefull...
http://www.tranexp.c...rom=che&to=eng  :P

so I only read schematics  ;)

[AndrewMartens]

mrcam,
It does indeed look interesting, but the site and documentation needs translation for us monolingual types. The Data sheet for the YM2149 shows it to be pin compatible with the AY3-8910/12. It may do the same thing.

This is correct.  Several years ago I picked up a bunch of old audio ICs from VintageFunWorld (now closed), including this assortment of chips (plus a SID and a few POKEYs).  At the time I was looking at the YM2149 / AY-3-8910/12, and they are all essentially the same thing.  You'll need to make a 40PDIP to 28PDIP adapter board if you want to use the YM2149 / AY-3-8910 in a board designed for the AY-3-8912, though.

[lemonhorse]

thanks to the co-operation of nILS the MIDIBox AY 3 8912 BOARD is getting more and more real. I sent the Eagle files to mike and now I'm looking forward to receive two testboards for nILS and me. 

the MIDIBox AY 3 8912 USER DETUNE MENU is working now => http://www.midibox.o..._ay_3_8912_tune . In addition there is a new USER ENVELOPE MENU info page => http://www.midibox.o...3_8912_envelope



best regards,
- lemonhorse

[lemonhorse]

You'll need to make a 40PDIP to 28PDIP adapter board if you want to use the YM2149 / AY-3-8910 in a board designed for the AY-3-8912, though.

good to know!

[AndrewMartens]

Assuming that down the road you plan to provide PCBs for people, one option would be to have the 28- and 40-pin layouts side-by-side  (ie; one row of 28 pins, one of 40, space, one of 28, one of 40) so that the user could simply solder in a socket for whichever size they had - without needing to built their own adapter board, or using point-to-point "dead bug" wiring.  The downside is that (assuming you have a 28-pin device), you're paying for 40 useless holes per board.

Looking at the datasheet, the footprint difference between the AY-3-8910 and -8912 is somewhat compatible, though not perfect.  This approach might work with only a few jumpers required on a single-sided board.

[lemonhorse]

Hi Andrew,
for practical reasons i would prefer a discrete adapter board solution for the YM2149 / AY-3-8910 chip (for a jumperless ready to use and small AY 3 8912 board).
But it would be great if someone would design, test and release a YM2149 or a AY-3-8910 adapter solution 

For now I'm waiting for the AY 3 8912 board from Mike. After a successful testing I will release all the relevant details.

[nILS]

Yay :-)

[vedge]

Hi

I also have 9 AY 3 8910 units that are sitting in a tube, so it might come in handy.

[jackies]

This is sweet!
I have one AY 3 8912 laying around somewhere...
May the 8 bit force be with you!!!

[lemonhorse]

Just to inform you: Mike is on vacation till the end of this week. So there is a little delay of the AY 3 8912 board.

Hardware Update:
MIDIBox AY 3 8912 Mixer > Added a MASTER VOLUME POT:
==> http://www.midibox.o...ay_3_8912_mixer

[lemonhorse]

got a mail from mike today - he told me that the two AY 3 8912 test boards are almost on the way.