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View topic - SMS FM Sound Expansion Boards (available now)

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  • Joined: 01 May 2012
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Post Posted: Thu Jun 14, 2012 12:51 pm
A couple of days ago I got my smsfm board and today I installed it, FM works and gets detected but I am having a buzzing background noise that is very annoying LOL

Here is the whole story:

I have rgb modded my sms2 as per these instructions: http://mmmonkey.co.uk/console/sega/sms2-av.htm

I have installed the SMSFM board but I got no sound at all when the SMSFM is enabled. Naturally that was because I was getting the sound before the smsfm board, mmmonkey's instructions grab the psg sound before the cap you need to remove...
so I just soldered my audio cable (the one that goes to the din8 plug so I can use an rgb cable) to the red wire of the smsfm output.
That results to an annoying interference , I get a constant buzzing that is getting louder or softer depending on what the screen displays and it does not matter if SMSFM is on or off...
Is there something specific to look for this buzzing?
Before the smsfm board I had no buzzing parasite in my output.
I am sure I am missing something, but I can't quite put my finger on it :)
Any help will be appreciated :) thanks!
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  • Joined: 31 Oct 2007
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Post Posted: Thu Jun 14, 2012 1:09 pm
This is video noise that you are getting. Not quite sure what to do to avoid it though...
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true
Post Posted: Thu Jun 14, 2012 1:55 pm
TmEE wrote
This is video noise that you are getting. Not quite sure what to do to avoid it though...


you are the second person telling me this today (was talking to a friend on msn that has a SMSFM installed in his SMS1 console and was getting video noise on his PCE console but not as loud as my sms2...) and I am puzzled why it appeared now... is it because of sms2's "cheap" design? You add something extra and the whole thing goes crazy?
With just the rgb-mod I had no video noise btw, I will try and feed smsfm's red wire directly to my rgb amp and skip the sony encoder , maybe it will help... dunno


edit: I have completely removed the SMSFM board and still getting said "video noise" at a softer volume....

edit2: playing wonderboy III with FM sound... the buzzing is just terrible :(

I made a video with my phone: , I even "upgraded" my rgb scart cable to be fully grounded, every ground pin is now connected, it did not made a difference sadly
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  • Joined: 30 Jan 2007
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Post Posted: Thu Jun 14, 2012 7:46 pm
Perhaps your SMS might be in need for a recap? I had a Japanese Mega Drive that had pretty noticeable video noise through the audio and recapping it almost entirely eliminated it.

Also, I assume you have ground connected on the FM board properly?
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Post Posted: Thu Jun 14, 2012 8:15 pm
Ofcourse the smsfm board is grounded nicely with a thick multi-threaded wire :)
I just made a random discovery :
if I bridge the RED + WHITE wires on the smsfm audio cable (either at the ex-cap point or on the smsfm board itself) the buzzing noise disappears and I hear clean PSG and FM sounds (tried with alex kidd and wboy3 FM patched) , the second I connect those points together everything gets back to normal. Removing the bridge makes the buzzing noise appear again until those 2 points get connected again. I have tried it "live" while the system was running....

I have no idea ATM why this is happening... I am open to suggestions.

As for the recap , I would like to avoid it atm since I did not had any serious problems until now, both sound and rgb picture was very good...
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  • Joined: 06 Apr 2011
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Post Posted: Sun Jun 24, 2012 8:05 am
I received my board yesterday \o/

I have a French SEGA M4 powerbase/NTSC and I have no idea yet on where to replace the capacitor on the main board.

Are there any users who have experience adding the FM board to this version?
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  • Joined: 31 Oct 2007
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Post Posted: Sun Jun 24, 2012 7:26 pm
That yellow wire goes to a cap that one was to remove and solder in the wires.

That SMS is cool, RGB only. I have seen a MD like that, except it still had CXA but solely for buffering RGB lines.
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Post Posted: Sun Jun 24, 2012 7:34 pm
TmEE wrote
That yellow wire goes to a cap that one was to remove and solder in the wires.

That SMS is cool, RGB only. I have seen a MD like that, except it still had CXA but solely for buffering RGB lines.


Thanks for the tip. I'll investigate.
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  • Joined: 01 Jul 2012
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Post Posted: Sun Jul 01, 2012 4:48 pm
@zipper

I have the french m4 powerbase mainboard too - and I want to install 50/60hz switch and the FMboard I've got lately - can you send me front and back mainboard photos of yours please? cause then I can solder it too :)

@TmEE

which cap do you mean exactly? C37?

cheers
cnt64
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Post Posted: Sun Sep 23, 2012 4:21 am
Hey viletim, I just sent you an email regarding the FM expansion board. I'll pay you immediately if you have them in stock. Thanks.
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  • Joined: 12 Oct 2012
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Post Posted: Fri Oct 12, 2012 1:05 pm
Hi viletim, I just sent you a PM about purchasing an FM board. I can pay immediately, so please just let me know how to proceed.

Thank you!
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  • Joined: 12 Oct 2012
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Post Posted: Wed Nov 07, 2012 12:46 pm
Hi, I just emailed you to put in an order for a board. Please respond with the details.

Thanks again!
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Post Posted: Wed Nov 14, 2012 9:56 am
TmEE wrote
That yellow wire goes to a cap that one was to remove and solder in the wires.

That SMS is cool, RGB only. I have seen a MD like that, except it still had CXA but solely for buffering RGB lines.


Ok. After some attempts I have found out how to add the FM board to a PAL M4 SMS.

Remove C49 cap (very close to the AV din connector and solder the red/white. Ground the board on one of the near solder points of the (missing) antenna unit.
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  • Joined: 24 Sep 2006
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Post Posted: Sat Jan 26, 2013 6:23 am
I updated the first post.

New version with region mod built in is now available.
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Post Posted: Sat Jan 26, 2013 9:27 am
Sounds good to me! (no pun intended)
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Post Posted: Sat Jan 26, 2013 11:48 am
I'm really interested in one of these boards but I'm crap at soldering... Is the soldering for audio mixing required or is that only for Alex Kidd and the Lost Stars? What happens if the audio mixing soldering isn't done? thanks in advance.
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Post Posted: Sat Jan 26, 2013 11:51 am
If you have a Master System (model 1) there are only 3 solder points to do, the FM board itself plugs into the back of the console. Is literally a 10 minute job. The SMS2 however, put aside an hour or so to solder one in.....
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Post Posted: Sun Jan 27, 2013 7:09 am
Hot_Violet wrote
I'm really interested in one of these boards but I'm crap at soldering... Is the soldering for audio mixing required or is that only for Alex Kidd and the Lost Stars? What happens if the audio mixing soldering isn't done? thanks in advance.


If you don't solder the audio wires you won't get any FM sound... but like omp said - It's not particularly difficult to do, even if you have never soldered before.
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Post Posted: Thu Jan 31, 2013 11:16 pm
Thank for replying (and explaining!) to my last question. I now have another silly question before I decide to buy one of these boards. I note that the 3 way switch goes between PSG/FM/JPN FM. I presume the 3rd position (JPN FM) is only a language switch and doesn't affect the console's running frequency. My question is this: If I fitted this board and switch and if I can find a guide to add a 50/60Hz switch for my SMS 1 (easier said than done!) will that combination cause any conflicts that you know of?
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Post Posted: Sun Feb 03, 2013 12:33 pm
Hot_Violet wrote
Thank for replying (and explaining!) to my last question. I now have another silly question before I decide to buy one of these boards. I note that the 3 way switch goes between PSG/FM/JPN FM. I presume the 3rd position (JPN FM) is only a language switch and doesn't affect the console's running frequency.


Correct.

Hot_Violet wrote
My question is this: If I fitted this board and switch and if I can find a guide to add a 50/60Hz switch for my SMS 1 (easier said than done!) will that combination cause any conflicts that you know of?


It will work equally well at 50 or 60 Hz. Be aware that if you have a PAL console and you switch it to 60 Hz, you will need to connect it to your TV with an RGB video connection. The composite video and RF connections will most likely lose colour in 60 Hz mode. Though this isn't related to the SMSFM board.
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Post Posted: Mon Feb 04, 2013 1:20 pm
Has anyone had any luck with Zillion II on the newer boards? I've still got the v1.0 board (without the fix) and all I'm getting is PSG sound. I've tried the hold-left workaround, but no dice.
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Post Posted: Sat Feb 09, 2013 7:58 am
Hot_Violet wrote
Thank for replying (and explaining!) to my last question. I now have another silly question before I decide to buy one of these boards. I note that the 3 way switch goes between PSG/FM/JPN FM. I presume the 3rd position (JPN FM) is only a language switch and doesn't affect the console's running frequency. My question is this: If I fitted this board and switch and if I can find a guide to add a 50/60Hz switch for my SMS 1 (easier said than done!) will that combination cause any conflicts that you know of?


Yeah there are SMS games who can become English or Japanese. Cloud Master notably wasn't released in Japan! (making its JPN dialogue inaccessible legit)

SMS regions were later inherited by the Mega Drive, so they take effect using an adapter too.
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Post Posted: Sat Feb 09, 2013 6:54 pm
ptepid wrote
Has anyone had any luck with Zillion II on the newer boards? I've still got the v1.0 board (without the fix) and all I'm getting is PSG sound. I've tried the hold-left workaround, but no dice.


I tried it yesterday, I have a v2.0 FM board, and it works, but the difference is hard to tell. The sound is less PSG-y (if that makes sense to you) for the music but the sound effects as well are a little too thin for my taste.
It seems like once a game switches to FM then it does not really use PSG, although I cannot rule out games that employ both so far with the few games I tried if I switch off the FM board not only the music stops but all other sound effects stop too, turning it back on gives me back music and sfx (but it may be due to the way the FM board works rather than game code because the audio is mixed by the FM board I am not sure it likes the live switcharoo, unless the mixing is really just voltage split thru the pot, in which case it could be independent from me turning on or off the FM portion).
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Post Posted: Sun Feb 24, 2013 5:38 pm
Well, I now know what I'll be buying with my spending money in March! Thank you in advance, VileTim!
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Post Posted: Fri Mar 01, 2013 1:51 pm
Will hopefully be insatlling the socketed version 2.0 into my SMS dunger tomorrow.

I will then have to find the time to do the solder ver 2.0 into another SMS2 (my current SMS2 has the ver 1.1 upgraded from the ver 1.0 in it) as I want to make a new modded SMS2 for myself (just do a few things differently).
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  • Joined: 10 Jan 2013
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Post Posted: Mon Mar 04, 2013 4:32 pm
I've just ordered my FM Sound board! I can't wait for it to arrive and to get it hooked up!
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Post Posted: Mon Mar 04, 2013 9:37 pm
Installed the socketed ver2 into my SMS over the weekend, very easy and nice to do 2 mod's (FM board and Mark 3/region switch) in one go!

Also replaced all the electrolytic capacitors and added the dual port pause mod.
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Post Posted: Wed Mar 06, 2013 2:07 am
viletim wrote
Hot_Violet wrote
Thank for replying (and explaining!) to my last question. I now have another silly question before I decide to buy one of these boards. I note that the 3 way switch goes between PSG/FM/JPN FM. I presume the 3rd position (JPN FM) is only a language switch and doesn't affect the console's running frequency.


Correct.

Hot_Violet wrote
My question is this: If I fitted this board and switch and if I can find a guide to add a 50/60Hz switch for my SMS 1 (easier said than done!) will that combination cause any conflicts that you know of?


It will work equally well at 50 or 60 Hz. Be aware that if you have a PAL console and you switch it to 60 Hz, you will need to connect it to your TV with an RGB video connection. The composite video and RF connections will most likely lose colour in 60 Hz mode. Though this isn't related to the SMSFM board.


I think it's worse for a NTSC console, technically. You'd get some kind of invalid NTSC 50 with composite video and RF.
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Post Posted: Mon Mar 11, 2013 11:19 am
I just took the plunge and ordered a board for my SMS I. I'm really looking forward to it. :)
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Post Posted: Mon Mar 11, 2013 11:20 am
omp wrote
Installed the socketed ver2 into my SMS over the weekend, very easy and nice to do 2 mod's (FM board and Mark 3/region switch) in one go!

Also replaced all the electrolytic capacitors and added the dual port pause mod.


Can I ask, what's the dual port pause mod? I'm planning on adding a pause button over the next couple of weeks since I'll have my SMS in bits doing the FM board mod and you've piqued my interest here. :)
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Post Posted: Mon Mar 11, 2013 9:19 pm
Hot_Violet wrote
Can I ask, what's the dual port pause mod? I'm planning on adding a pause button over the next couple of weeks since I'll have my SMS in bits doing the FM board mod and you've piqued my interest here. :)


The dual port pause mod uses a NOR gate to operate the consoles pause button.

Info here
http://www.smspower.org/Development/JoypadPauseButton

Note there is an error in that guide, pin 14 is +5v pin 7 is GND.

Alternate single port pause mod uses a OR gate

Info here
http://www.smspower.org/smscartpad/pausebtn.htm

These work well, but can be a bit "buggy" ie when you pause/unpause sometimes your character (or whatever) may go in one direction. For example when I did it to my SMS with Hang on built in when you pause/unpause (via the controller pause button) the bike leans to the left. But I used left + right, perhaps if I used up + down it wouldn't be so much of an issue...ah well maybe one day I will re-wire things (easy) but it doesn't bother me to much, just got to be aware of it.If I do a re-wire it means I have to change my SMS2, the above mentioned SMS as well as my consolized GG, also the 3 or 4 control pads lol!
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Post Posted: Fri Mar 15, 2013 4:39 pm
Thanks for the fm board, Viletim-It sounds awesome!

Do you guys think that it is important to tweak the mixing pot? It seemed like wonderboy iii psg may be too loud, but I don't want to mess with it if I don't have to.
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Post Posted: Fri Mar 15, 2013 10:00 pm
futureman wrote
Do you guys think that it is important to tweak the mixing pot? It seemed like wonderboy iii psg may be too loud, but I don't want to mess with it if I don't have to.


Adjust it if you like - that's what it's there for. The level of the PSG is not the same accross all Master Systems/Installation methods. The trimmer pot alters the volume of the FM sound only, the PSG level is not changed by the board at all.
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Post Posted: Mon Mar 18, 2013 5:58 pm
I got my FM Board in the mail last week. A couple days ago, I got it installed and it works great! Thank you so much, VileTim! This is such a wonderful service you provide to the community!

Actually, I'm planning a Youtube show on retro gaming, and one segment involves telling people about special products made for the retro gaming community.

Would you be OK with me doing a spotlight on your FM Sound Boards?
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Post Posted: Tue Mar 19, 2013 12:37 pm
Arjak wrote

Would you be OK with me doing a spotlight on your FM Sound Boards?

Of course! Post a link when it's ready if you like.
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Post Posted: Wed Apr 03, 2013 6:40 am
phoenixdownita wrote
ptepid wrote
Has anyone had any luck with Zillion II on the newer boards? I've still got the v1.0 board (without the fix) and all I'm getting is PSG sound. I've tried the hold-left workaround, but no dice.


I tried it yesterday, I have a v2.0 FM board, and it works, but the difference is hard to tell. The sound is less PSG-y (if that makes sense to you) for the music but the sound effects as well are a little too thin for my taste.


Just got my v2.0 board today so I got to try this myself. Zillion II now definitely works with FM sound. WB3 and Time Soldiers of course now work automatically. Thanks again Tim!
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Post Posted: Thu Apr 04, 2013 3:41 am
I just ordered one today. I cant wait to get it. :)
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Post Posted: Tue Apr 16, 2013 7:13 am
I just received the FM soundboard today. That was fast shipping! I'll install it tomorrow or the next day when I get some free time, and I'll post my impressions soon after. :)

***UPDATE***

I just installed it and I am very satisfied. Thanks Tim!!!
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Post Posted: Thu Apr 18, 2013 7:13 pm
In case anyone is curious, I recently installed one in my Mark III and it works great. Of course, you'll want to get the solder-in version since the Mark III's expansion port is totally different than the SMS's. You can get all but three of the needed signals for the FM board from the expansion port but you'll need to grab the other three from the Z80.

For the audio, what I did was cut the trace for the audio output (the PSG goes through a buffer before it goes to the RF modulator and AV port) and then soldered the input/output wires of the board to each end of the broken trace.

One last thing is that the region switching doesn't work on the Mark III since it handles region switching differently than the export SMS. Still, having viletim's FM board is a much better option than tracking down an FM unit since it's all internal, much cheaper, and you still have RGB available.
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Post Posted: Thu Apr 18, 2013 10:24 pm
Well, I got mine a couple of weeks ago but only just got time to fit it. All's working well and it's a fine addition to my SMS. Thanks. :)
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Post Posted: Fri Apr 19, 2013 4:46 am
I saw the previous posts regarding the possibility of connecting it to the megadrive.
I have one question. Can the module be left connected when playing mega drive games or is it required to disconnect it?
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Post Posted: Fri Apr 19, 2013 5:14 pm
I absolutely love this addition to my SMS. It's got me playing it more than ever and giving games a chance that I've owned for 20 years but never played.

I have one question though: exactly what kind of toggle switch is used? The online install guide just calls it a "three position switch." Is it "ON-OFF-ON", or "ON-ON-ON"?

I want to replace the toggle with a slide switch because I hate the look of toggles so I never use them for these things. Right now, my toggle is just resting inside the expansion board cover.
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Post Posted: Sun Apr 21, 2013 9:51 am
kamillebidan wrote
I saw the previous posts regarding the possibility of connecting it to the megadrive.
I have one question. Can the module be left connected when playing mega drive games or is it required to disconnect it?


It should be ok to leave it connected all the time as long as you remember to switch it off when playing Mega Drive games.


Kevinmos3 wrote

I have one question though: exactly what kind of toggle switch is used? The online install guide just calls it a "three position switch." Is it "ON-OFF-ON", or "ON-ON-ON"?


It's ON-OFF-ON (and written on the side of the switch, in fact).
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Post Posted: Sun Apr 21, 2013 10:29 am
When I integrated a YM2413 mod to my MD2 I experienced freezing issues in MegaCD games and couple of MD games. When I popped the YM2413 out the socket then the freezes stopped. FM enable/disable did not make a difference in my case.
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Post Posted: Sun Apr 21, 2013 12:06 pm
Do you think connecting each data line through a JFET, with the gate connected to !S_RES could solve the problem? Or do you know any tri-state buffer which is bidirectional (is 74LS245 fine?) ?
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Post Posted: Sun Apr 21, 2013 6:49 pm
The YM is write only so you only need one direction only and 3state is not necessary. Stuff like 244 should do, but 245 has a nice flow-through arrangement on its pins so in makes life a bit easier.
I never got around to try this so I cannot say if it is effective but I believe it should be.
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Post Posted: Mon Apr 22, 2013 9:34 am
TmEE wrote
When I integrated a YM2413 mod to my MD2 I experienced freezing issues in MegaCD games and couple of MD games. When I popped the YM2413 out the socket then the freezes stopped. FM enable/disable did not make a difference in my case.


That doesn't make sense... The YM2413 only listens on the bus, it never writes to it. Perhaps it loads the bus, but according to the datasheet it has less leakage current that than your typical 74LS245 and not too much input capacitance... What else did you have hanging off the data bus when you had the problems (FM detection logic, etc)?

kamillebidan - If you have a Ver 2.0 SMSFM board then I would just connect it to the bus without any buffer. This board has the newer YM2413B which is much lower power than the original.
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Post Posted: Mon Apr 22, 2013 11:40 am
It certainly makes no sense, and all other stuff was also in listen mode all times. Only thing capable of driving the bus is the 244 and it most definitely sat in 3state all times.

http://www.tmeeco.eu/Fileden/YM2413SCHEM.jpg
YM2413SCHEM.jpg (300.31 KB)
YM2413SCHEM.jpg

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Post Posted: Tue Apr 30, 2013 7:31 pm
I'm looking forward to getting one of these. Looks like he is away right now? Anybody in the USA have any spares on hand? I just joined up today, but many of you already know me from Atari Age. This has me thinking about adapters for SMS / Genesis to hook up to an external midi instrument like a keyboard, or Roland Sound Canvas etc... Anybody work on anything like that thus far?

Thanks,
AX
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Post Posted: Tue Apr 30, 2013 7:42 pm
Little-scale has made MIDI stuff: http://little-scale.blogspot.com
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