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Mega ST project

Posted: 11 Sep 2021 06:58
by HigashiJun
Ok, so while still slowly but surely expanding my 1040 STE I got my hands on a cheap Mega ST 2 I want to upgrade.

As stated in my previous post (https://www.exxosforum.co.uk/forum/viewt ... =23&t=4480), I had no luck with Exxos' 16 Mhz booster/TOS decoder board probably due to the IMP chips installed on the motherboard.

Not being able to get TOS 2.06 running on my Mega was quite bothering me, so I was looking for other solutions to overcome this issue.

Here is the solution I found and the remaining stuff to install:

Mobo.jpeg

As you can see, the motherboard has already an Exxos' 1.44 HD KIT, a STORM ST (8MB ALT RAM and TOS decoder), Exxos' Mega ST dualtos installed and also onboard memory upgraded to 4 MB.

Here are some close-ups:

HDkit.jpeg
AltRAMTOS.jpeg

Tested and works great. I have TOS 2.06 and the FDD is also working !

The next big step is to install the following add-ons:

Tweety.jpeg
HDD.jpeg
VGA.jpeg
PAK68.jpeg

I just hope to have time to close this project before Christmas.

Cheers.

Re: Mega ST project

Posted: 11 Sep 2021 10:22
by Badwolf
MegaMega ST if you fit all that in! :-)

BW

Re: Mega ST project

Posted: 11 Sep 2021 11:44
by JezC
Looks like a really ambitious upgrade!
Have you included an upgraded PSU for all that extra circuitry?

I'll be following your progress with great interest

Re: Mega ST project

Posted: 11 Sep 2021 12:51
by HigashiJun
Hope I can make the PAK68 work and then it would be a MegaMega ST. :D

Yes, the PSU is also upgraded with a STPSU and just in case I also have a 200W PIco PSU.

The Tweety Board is already fitted and I will post a picture tomorrow. Is is really pleasant to have stereo sound on the Mega ST.

Cheers.

Re: Mega ST project

Posted: 12 Sep 2021 04:25
by HigashiJun
Ok, here is the Tweety Board fitted:

Tweetyboard.jpeg

It is a tight fit with the PSU installed but it should be OK when closing everything back.

I will also have to think where to secure this board once the other add-ons installed.

Re: Mega ST project

Posted: 13 Sep 2021 09:19
by Darklord
If you plan on playing any games then make sure you install the switch for the
Tweety board that lets you revert back to the original.

It's because certain digital samples in games do not play well with the Tweety
board. They will sound "wrong".

So if you have the switch... :)

Re: Mega ST project

Posted: 13 Sep 2021 11:14
by HigashiJun
I would like to use this Mega for more serious things and play games on my 1040 STE, but who knows... :D

Could you tell more about this famous switch ?

Re: Mega ST project

Posted: 13 Sep 2021 18:19
by Darklord
HigashiJun wrote: 13 Sep 2021 11:14 I would like to use this Mega for more serious things and play games on my 1040 STE, but who knows... :D

Could you tell more about this famous switch ?
I think it's actually in the Tweety board docs... Do you have them?"

Here is a message thread that might help...

https://www.atari-forum.com/viewtopic.php?t=31562

Re: Mega ST project

Posted: 13 Sep 2021 18:41
by DoG
The docs for Tweety Board is here.

Re: Mega ST project

Posted: 13 Sep 2021 22:19
by HigashiJun
Darklord wrote: 13 Sep 2021 18:19
HigashiJun wrote: 13 Sep 2021 11:14 I would like to use this Mega for more serious things and play games on my 1040 STE, but who knows... :D

Could you tell more about this famous switch ?
I think it's actually in the Tweety board docs... Do you have them?"

Here is a message thread that might help...

https://www.atari-forum.com/viewtopic.php?t=31562

Yes, I have a PDF version oh the document but I do not remember any statement concerning a switch.

I will check again.