Granlunds FrankenSTein

[agranlund]

Wish I would have documented my ST upgrades from the beginning! Starting one of these members blogs as an incentive to do so for future upgrades
My machine is one of these early 520ST models and it's been in my possession since new back in the 80s.
I just couldn't bring myself to chuck it away so I'm using it now as an excuse to do some electronics and programming projects.

What's been done to it so far:
TOS: upgraded from stock 6Chip TOS 1.00 to 2chip eeproms that can run either 192Kb or 256Kb.
Currently switchable between EmuTOS and TOS 2.06.

Blitter: Self made Blitter expansion for the CPU socket, with 256KB ROM decoder and IDE interface.
(This IDE interface is no longer in use)

RAM: Exxos 4MB ram upgrade.

CPU: TF534 accelerator with 68030@50Mhz. The card pretty much worked out of the box with just very minor Atari tweaks.
Most of the effort was writing the necessary Atari software to make the machine take advantage of the card properly.


Here's an early one with Blitter, IDE interface, 4MB and a pretty crude TOS ROM conversion using sockets and wires.
I was very happy about this

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The current setup, added PCB for the TOS roms and of course the mighty TF534.
The Blitter is still there, hiding under the the TF.

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I have a bunch of more things in mind for the machine and I'm not really sure when this is going to end - presumably when the computer finally gives up and explodes


These are the more realistic things I have in mind next:
- Add realtime clock to blitter board (same as Mega to keep it simple)
- Make a PCB for where the RF modulator (and monitor socket) used to sit.
This will host UBE switch circuitry, VGA + Audio connectors + stuff yet to be fully decided.. the board can be quite large so there is plenty of rooms for more stuff. Thinking of one of those small midi modules. Perhaps internal speaker.
The old holes in the case needs to be filled and new ones made ofc.

[terriblefire]

You need an H4!

[ube]

This is pretty much my blue-print for my ST. Plus an internal Microcosmos and a micro-gotek (can't remember the name of the product). Oh, and a tf536.

[Steve]

That is really awesome! With all that CPU power it just needs some kind of FPGA implementation of a high resolution graphics card. It would be a Calamus monster ;D

[agranlund]

That is really awesome! With all that CPU power it just needs some kind of FPGA implementation of a high resolution graphics card. It would be a Calamus monster ;D

I was actually toying with the idea of building a miniaturised VOFA adapter a little while ago, but I'm not really sure what I would use it for so it's on hold
The graphics card will just barely fit

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For what I'm doing now I'm really happy with using the ST resolutions with the amazing UBE switch.
Running the desktop in mono and launch games or whatever I am working on in colour mode.
I've modified the switch and firmware a tiny bit to switch mono/colour based on HSYNC timing instead, this lets it do it's thing before TOS has a chance to react - preventing it from restarting the machine without needing any software to override the VBL handler.

Works well with games that aren't trying to be clever and detect mono but simply does SetScreen (appears to be most of them).
Not a universal solution by any means, and some software still require rebooting in color mode, but it's good enough for me

[agranlund]

You need an H4!

I know, right!! Had some very close calls, but have been able to resist building one so far
Also been way to tempted in making some serious efforts getting hold of a stock Falcon but I'm resisting it so far..

[agranlund]

This beauty arrived in the mail today! Thank you Terriblefire

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Fun for the weekend

[agranlund]

It has begun!

Now, where can I get hold of an ST firmware for this beauty? (@terriblefire)

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Cheers,
--Anders

[terriblefire]

Oh let me get this monster to bed and i'll find you an ST firmware.

[terriblefire]

Try this for a starter for 10.

tf536r2_main_top_ATARI_FULL_PHASE_7_28_6_2020.zip

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