HOTFIXES for Older Cards Only, also for Tandy Lo-Tech Audio Compatible Card!!! has same bugs!:
68nf on SN76489, 2k2 Resistor on SN76489.

If you don`t add 2k2 Resistor you will get problems running Card together with a Soundblaster or maybe some other Cards on AT.. also some bios software get stuck until mcu circuit unmutes sn76489 (AT only)

2k2 from VCC to READY on SN76489.
68pf from 7 to 9 on SN76489. -> Fixes some Noise

Thanks Matze79 for the beautiful card, it works perfectly !
Highly recommended.
Here's a demo of Zeliard with TNDY card : https://youtu.be/CMAuSe2x4pQ

Finally, my kit arrived as well. Will try to assemble it and put out a video over the next week. 😀

Glad you got it 😀

Sorry for the messy Papersheet.
I had no better Idea 😁 as i have all parts in tubes.

Got my card tested and working as well! Thank you Matze!

I got a 2nd bracket not sure if that was on purpose, but I dont think I need two. So if someone needs a spare bracket PM me.

This is Hot Spare ;D
you may want to keep it, for future replacement.

Is it possible to get Lemmings to use the Tandy sound? It has two sound drivers as far as I can see: ADLIB.DAT and TANDYSND.DAT. However I feat that only TGALEMMI.EXE will use the tandy sound. Is that right? Would love to try Lemmings on the TNDY card...

Did you try copying TANDYSND.DAT over ADLIB.DAT ?

i have no idea i never tested Lemmings.
Several Games will only work with Tandy Graphics.. maybe some day one creates a FPGA based TCGA Card ;I

Good idea. I‘ll try that. Supposedly the DAT files are basically COM binaries with the music data attached. Offering an API at int 61h to play the music. See also here:

https://github.com/tomsoftware/lemmings_music_player

If it checks Machine Byte or some kind of detection it will also not work 😉

You can also play the Lemmings MIDIs on the Card:
PX Player: play MID and XMI files under DOS
PX Player: play MID and XMI files under DOS

And here are the MIDIs:
http://www.lemmingsuniverse.net/downloads.html

EDIT: Ohh the MIDIs are no longer on the Site..

Jan is now trying to add support for machinebyte / string to the driver..
so more games will be able to run.

ERRATA:

The printing on the Card is wrong for Jumper Settings.

Update:
1E0h: JP2 1-2,3-4 JP1 2-3

Good news: I assembled my TNDY board. Went relatively well. The card seems to work as well. Outputs sound, but the bad news: it induces graphical glitches and system instabilities. Did anyone else have such problems? I tried on port 0C0h, but also on 2C0h and other ports with the tndy.com port remapper.

Anyone else also owns a ET4000 and can test this ? currently only ET3/4000 users are Reporting Issues ?!?

I tested at least 4 Machines and some playing Tunes for Days.. and had not a single Issue 😒
I also can not replicate this Problem yet.

Maybe someone can borrow me a ET4000 Card to test it soon..

matze79 wrote:

Out of Stock. 😀 others will have to wait some time 😀

I would still like one as well.

And my video on the topic: https://youtu.be/d5Kv4okRACw

The card will be overhauled and hopefully be even better. 😀

Maybe some words here..

if you use TNDY.COM you have to expect weird Behavior because of how the TSR works.
Also its still in development.
It has the same Limitations like TEMU and VSB.
On some Machines it will work good, on others it will not.

For example, Smartdrv is incompatible and conflicts with TNDY.COM

If you have QEMM you can also try this TSR:
https://github.com/pdewacht/lotech

DragonSphere is trying to implent a Driver that does not need QEMM386 but this also has its disadvantages.

You have to expect weird Behavior if you use this Card on AT Machines configured at 0C0h,
because the Second DMA Controller is at this Address.
I did not have such Problems yet, except for Duke Nukem 3D not detecting a Soundcard correctly.

A Tandy does not have a Second DMA Controller, and later Tandys with Controller use other IO adresses.

So there is indeed some small issue but i`m sure we can rule it out.
the majority of machines seems to work just fine.
i have at least installed 4 cards for testing purposes in different systems
ranging from Nec V20 to Pentium 2.

And no one shows this glitch.
That makes it difficult to track it down without replicating the issue.

Fact is if we remove the Latch, it does no longer occur.
But on my Systems this is no issue.
Also on Dreamblasters Machine all works as intent.

Hopefully my spelling is ok, if not please correct me 😀

Demo of Matzes Tandy ISA card on my 386, running Maniac Mansion (patched "modiac" version) :

https://youtu.be/wZ8DCc6qfPQ

Works great ! 🤣

Is there any reference in datasheets or other tech docs for the capacitor on SN76489 pin 7 to 9? SN76946 datasheet only recommends 10R & 0.1uF RC from output to ground.

This is something I discovered myself years ago when experimenting, it serves to stabilise the internal amplifier so it wouldn't oscillate so much. Same thing as placing a small value capacitor over the feedback loop on any normal opamp circuit to conserve gain for the freqs that matter or to just form a lowpass filter by leaving high freqs with gain of 1 while stuff of interest gets different gain. End result is much lower magnitude of the oscillations at signal edges and in theory much reduced distortion and maybe even less noise.