Hello, welcome back to the 8-Bit Guy. So, in a previous episode, I covered this little
guy here, which is a clone of the Covox Speech Thing. And I was pretty excited about this
because it finally allowed me to be able to use my 486 laptop, which is my favorite DOS
gaming laptop, and actually get some kind of sound other than the PC speaker sound.
Now, you know, it doesn't work with all games. But it works with quite a few, whether
I'm using the covox or the Tandy emulator. But, shortly after I did the episode on this,
the same guy that created this, sent me an email and asked me, says "Hey David, what
would you think if I could put an Adlib on a similar type parallel card?" And I said,
"Well, you know, that's pretty cool. Actually, I have no doubt you could put the Yamaha YM3812
chip on a card like this." But, I had serious doubts whether or not you'd be able to get
it to work with existing DOS games. Well, I recently received this in the mail. Now,
he claims he's done it and so what I'm going to be doing is I'm going to assemble
this card and I'm going to hook it up to my favorite 486 here and we're going to
find out "does it work?" Let's get started! All right, so let's see what's in the
kit. There's quite a few little parts, but it doesn't look too daunting. Here's the
actual circuit board. And this, of course, is the main component, the Yamaha YM3812.
It's hard to believe you can still buy these chips brand new. I'm not sure what they
are used for these days. But this is identical to the one made back in the 1980s. You could
put this chip in an original ad-lib card, or one of these old Yamaha keyboards and it
would work just fine. I'm going to go ahead and assemble this, if you don't want to
watch the assembly, just skip forward to about 8 minutes 30 seconds. He sent me these documents.
He said he was working on some better assembly instructions for future customers, but I actually
received one of the first prototypes, so this is what I get to work with. However, it isn't
that hard to figure out. These are all capacitors because they start with C. J usually means
some kind of jumper, and R is for resistor, and so on. So the way we do this is look at
this diagram and pick a part. This one, for example, shows to be C3, and we can see over
here on the bill of materials that C3 is this part here. I'm going to start with this
socket. I like to start with the shortest components first, for various reasons. What
you need to make sure on these sockets is that you find the little notch and line it
up with the notch that is etched onto the board. Another thing I do is solder two opposite
pins of the socket in place first. That way I can turn it around and double check that
it is completely flush with the board and also double check the notch is lined up one
more time before soldering the rest of the pins. I guess I can take this opportunity
to mention something. Every time I do a soldering episode, I get a a few criticisms from people
on my soldering technique. Everything from the temperature of my soldering iron, to the
fact that I let the solder touch the tip of the iron, and even people complain of the
way us Texans actually pronounce the word solder, because we leave the L silent. So
I can just say right now that I've never claimed to be an expert at this. I never had
anyone teach me to solder. I had to learn how to do all of this when I was about 12
years old, and so much like my programming techniques and my musical skills, they're
all self-taught. I do what works best for me. I make no claim in my videos that it's
the right version or the best way to do stuff, so that's my disclaimer. Apparently my camera
wasn't running when I soldered this USB power port, but it was probably the toughest
piece on the board because the little pins are so small. Moving along, I'm going to
do this crystal next. There is no specific orientation for this. It fits in there nice
and flush. I'll bend the pins out a little to hold it in place while I solder. And there
we have it. All that is left is to cut the excess leads off with some wire cutters. The
next part I will install is this little 14 pin IC. There's no socket for this one.
But you still need to be sure to line up the notch on the chip so you know it is in the
correct direction. One other problem you might notice is that the legs are just a bit too
wide to get it to fit down in the board. So, one trick I usually do is press the chip up
against the workbench surface until they bend inwards just slightly. I do this on both sides.
Now it will be much easier to fit it in there. There we go, just need to solder all of those
legs. So if you are wondering why I do the shorter components first, the main reason
has to do with making it easier to solder. Because, when I turn the board upside down
I want the part to stay in place, but if there were taller objects on there already, then
parts would fall out unless you held them in place somehow. Next up is the reset switch.
It apparently needs this because the synthesizer chip is powered externally. So if you turn
off the computer in the middle of game, the notes will just hang rather than shut off.
So you can just press this button to reset the chip. Now, you might be thinking the orientation
of this button would be confusing because the pins look like a square arrangement. However,
they are just slightly rectangular, so there is no way to put this in the wrong direction.
However. It does require some force to snap it down in there. Next, I'm going to do
these little resistor packs. These do have a specific direction they go in, so you have
to pay attention to this little dot that represents pin 1. Then, on the board pin one is the one
that has the square etched around it. So the first one goes here, and the other resistor
pack goes over here. And next up, I'll be putting in the headphone or line output jack.
My understanding is it is amplified enough to work for either one. And it goes right
here on the board. OK, I'll solder that in now. All right, I'm going to do the resistors
next. Now, fortunately, he has labelled these with their values, which is really nice for
me since I have problems reading the color codes on these. So fortunately I don't have
to get the meter out to read these. However, these do mount in a very unusual way. They're
meant to be vertically mounted. Let me pull these end pieces off here and I'll show
you what I mean by that. OK, so you need to bend these things all the way around 180 degrees.
Like this. Then you need to slide it down in the holes like so. This is done to help
make the board more compact. It solders in just like any other resistor, though. And
that's what a vertical resistor looks like, and that's pretty much how all of the resistors
are going to be mounted on this board. In fact, here you can see where I have finished
mounting all of the resistors. Next up are these disc capacitors. The print is too small
for my eyes, so I have to use a magnifying glass to see which values they are. These
just slide in, like so. They are not polarity sensitive so they can go in either direction.
There is one jumper on the board. I think this is for a bass boost option or something.
Anyway, it mounts right here like so. There are quite a few electrolytic capacitors, and
these do have a very specific polarity. You see the little white stripe there. That indicates
the negative side. That needs to line up with the thicker part of the circle. Also you might
notice that the shorter lead is also the negative. And when you're done with all of the capacitors,
it should look like this. Next I'll put in this LED. Now, you might be asking how
you can tell which direction it goes? Well, one of the leads is longer than the other.
That is the positive lead, and the shorter is the negative. Much like the capacitors
we just did. OK, so this is the last big component that I need to solder. It's just a matter
of lining it up popping it down in there. I should mention that these larger end pieces
don't actually conduct any signal, but they are used to carry the physical stress of the
connector, specifically when pushing in or pulling out a parallel cable. So you need
a big ole' blob of solder on these for structural purposes. And there you have it. Next I'm
going to insert these two chips, starting with the small one, paying close attention
to the orientation. And, of course, here comes the YM3812, the main attraction in this build.
And there you go. You might think we're done, but there's actually one more part.
And this is the only part I'm not fond of. And the reason I'm not fond of it is due
to how it goes on here. You can see right here, that's where it goes. What you have
to do is bend these pins out 90 degrees, like so. And then it goes in like this, and yeah,
it just hangs off the side like that. OK, time to test this thing out. I'll use my
favorite 486 laptop, who's only downside is a lack of a sound card. For power, I'll
use this standard USB cable and an iPhone charger. Rather than plugging in speakers,
I'm going to connect it to this USB audio recorder so we can a clear recording of what
comes out of this thing. All right, let's see what happens. A test program is included
that makes it really simple to tell if the board is working or not, it's called OPL2TEST.
Woo Hoo! So it looks like my board is working. Before we go any further, I need to explain
a few things about the design, and let's start with some terminology. This product
is called the OPL2LPT, and I should probably explain why. The OPL2 refers to the type of
sound chip, and the LPT is an old MS-DOS term and it refers to Local Print Terminal, or
basically a parallel port. Now, let's demystify the terminology on the sound chip. The Yamaha
YM3812 is an FM synthesizer chip, but it was also nicknamed the OPL2, which stands for
FM Operator Type L, version 2. It was used in famous sound cards starting with the Ad-Lib
and eventually in other cards like the Sound Blaster and Pro Audio Spectrum. Later on,
Yamaha came out with the YMF262 which is a backwards compatible chip, but offering more
voices and waveforms than the earlier design. This was nicknamed the OPL3 and it was used
in cards like the Sound Blaster 16, Pro Audio Spectrum 16, and clones such as the ESS audio
drive or Crystal Audio. And even though both chips are technically Ad-Lib compatible, the
vast majority of DOS games only made use of the original OPL2 chip. And this is the chip
that is featured in the product I'm about to demonstrate. First of all, there are literally
zero MS-DOS games that will work with this natively. The Ad-lib card was always expected
to be found on the computer's main bus at port 388. But the parallel port is expected
to be found at port 378. So how do we correct for this? Well, there are a few different
ways to make this work. At the moment, the most practical way is by using the driver
that is included. You'll need to start up before you play your game. What it will do
is intercept all of the attempted writes to port 388 and redirect them to port 378 instead.
So, that's what I'm going to try first. The first thing I'll need to do is start
up the driver. You can add this to your autoexec if you don't want type it in every time.
OK, that's started. Now, I'm going to load one of my favorite DOS games that has
really good music. All right! This is freakin' amazing! I've never heard music like this
come out of my 486 laptop. And this sounds absolutely perfect. This is not an emulation,
rather it's the real thing. You know, I might sound a bit like a heretic when I say
this, but I actually prefer the Ad-Lib music on Lemmings over the Amiga version. I've
spent plenty of my life playing both versions, and both are absolutely great. . But I think
the Ad-Lib with it's extra voices really makes this musical score shine. With the Amiga
having only 4 voices, one of them being needed for sound effects, left this music being essentially
3 voices. The Ad-Lib really pulls this off well! Although, admittedly the sound effects
on the Amiga were much better. I really loved the sound of the lemmings when they fell to
their death on the Amiga version. Here on the Ad-lib version they just make a little
splatting sound. OK, so onto another game. Atomino is one of those games that I absolutely
love and I've spent a lot of time playing the Amiga, DOS, and Commodore 64 versions.
Yet, when I ask other people about the game most people have never heard of it. But one
thing all 3 versions have in common is they have excellent musical scores that are really
well tailored to the hardware. Anyway, let's try one more people will be familiar with.
Oh man. I love the music in this game. And this is another where I think the Ad-lib version
actually sounds really nice, possibly better than all of the other sound cards. I'll
have to duck the tomatoes when I say I actually prefer it over the MT-32 version. Now, one
thing I should mention is that Ultima 6 only plays music through the Ad-Lib. The sound
effects always come from the PC-Speaker, which I've dubbed in here. Let's try another
game. This one is not heavy on music, but does use the Ad-Lib for sound effects. And
it seems to sound fine as well. Let me try shooting something so we can hear some more
sounds. OK, let's move along to something with more music in it. Sierra was one of the
first companies to really help push the Ad-Lib card into popularity by vowing to support
it on all of their games. And they did a pretty good job of utilizing it too. OK, so far just
about every 1980s game I have thrown at this thing works fine. So here's a thought. It's
not very well known, but the Ad-Lib card is actually capable of doing digital samples,
it just wasn't used very much because it doesn't have any sort of DMA so the CPU
has to do all of the work, much like doing samples on the PC Speaker. So, I thought maybe
we should try a few games that actually do use digital samples on the Ad-Lib. I'll
start with this one! And, to my surprise, it works perfectly. This game has no music
in it to my knowledge. Only sound effects. Let's try another game that uses both digital
music and sound effects, Pinball Fantasies. And, it also seems to be working perfectly.
It sounds a heck of a lot better than the PC-Speaker version.
Ok, so this little guy, along with the driver, worked with practically every game from the
1980s that I tried to throw at it. There were a few problems, though. There were a few games,
such as Tetris Classic that behaved strangely. Technically, the sound worked, but for some
reason it plays slowly. I mean, the tempo is just dragging here for some reason. The
music should be playing about 50% faster than this. However, all of the sound effects are
timed perfectly, so I have no idea what's causing this. So now let me give you the really
bad news. So, the driver does require a 386 processor. So, you can't use it with a 286
or an XT of any sort. And, this is due to some special features of the 386 processor
which allows it to essentially do some virtualization where it can intercept all of the calls being
made to port 388 and redirect them. Also, as a result of this, any games that require
386 enhanced mode to operate will not work with this driver. So, many of the games that
were made during the 1990s that require a more high-end DOS machine flat out aren't
going to work with this thing. However, not all hope is lost. There are still some possible
ways to make it work. And that's by patching the game. If you were to find the parts of
the machine code that actually write to port 388 and actually change it to 378 instead,
the game would not need a driver and would just natively write to port 378 on its own.
Let me demonstrate this with the game Heretic. So, you just run this ADPATCH program. So,
it looks like I need to add in a -I and the name of the executable. So let's try that.
OK, it says it is patching the game. Well let's see if it works. Keep in mind this
game would not work with the driver, and there is no driver currently loaded. And it does
appear to be working! Now, unfortunately, this game does not support sound effects on
the Ad-Lib, it requires a sound-blaster for that. But you can at least get the music,
which is more than I was able to get before. The patch program is in an experimental stage
right now and they're still working on improving it, so I imagine as time goes on it will support
more and more games. In fact, Heretic wasn't even on the list of games that they had confirmed
that it works with, but it still worked. I suspect they just hadn't tried that game
yet. Of course, there is another way to get this to work with more games, and that would
be to encourage developers who are still making DOS games today to actually add native support
for the device right into the code on purpose. One example is a CGA game that's in development
right now that supports it. It's called Castle Viana and it's in an early stage
of development but the author has pledged to support this device. And myself, I'm
planning on doing a port of my Planet X2 to MS-DOS, I'm actually already working on
that right now, and I plan to support this device natively in my code as well. One other
thing I wanted to mention about this board is you can actually run it off of any 5 volt
power source you want. In fact, he's even put these two little special solder pads right
here on the board so you could solder it up any kind of power source you have in mind.
You could even theoretically use the PS/2 port on your laptop computer for example,
if you didn't want to use an external power supply. All right, so you may be wondering
where you can get one of these magical devices. Well, if you happen to live in Europe, then
you probably should buy from Serdashop.com and I'll put a link down in the description
field for you. If you live in North America, then good news, I have them available in my
web store. I bought 40 of these from Serge and they are for sale right now both in kit
form and I've been soldering together some pre-assembled units for those people who don't
feel like soldering their own kits together. So you can buy it either as a kit or fully
assembled. Anyway, I don't know if 40 will be enough, I might sell out tonight, but if
I do, don't worry I'll get more. This is a product that I'm going to be carrying
from now on in my web store, at least until the new version comes out. Speaking of the
new version, Serge has been working on a newer version of this that uses the OPL3 chip. And
while not many games actually benefit from this version of the chip, the main advantage
is that it is surface mount and these can be assembled by machine, which would reduce
the cost and and time of manufacture. All of the OPL2 versions were either assembled
by hand or sold as kits like the one I got. No word yet on when that one will be available,
other than probably the first half of 2018. So if you really want one of these right now,
you might as well get the OPL2 version. Well, I guess that about wraps it up for this episode.
So, thanks for watching and stick around until the next one, and I'll see you then!
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