Finding this was lucky - Atari 800

[mrbombermillzy]

Unless just the temperature changes in the room are responsible?

Thats the one I would have thought to be the probable cause. We have just had splendid weather the last few days after all. :)

[rubber_jonnie]

Unless just the temperature changes in the room are responsible?

Thats the one I would have thought to be the probable cause. We have just had splendid weather the last few days after all. :)

I'd agree with the exception that our house has a quite stable temp range, but you never can tell.

[rubber_jonnie]

The 800 is up for surgery next :)

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This should turn it into something amazing and remove the need for the SDriveMAX by having the internal CF card a bit like SIDE carts on the XL/XE machines, plus a whole bunch of other upgrades.

I think it'll be my new favourite Atari :)

[HigashiJun]

My favourite Atari is still the Falcon.

;)

[rubber_jonnie]

My favourite Atari is still the Falcon.

;)

I grew up with the 8 bit machines before the ST's, the Falcon never factored in for me, so I have no desire for one. ST's on the other hand...

[HigashiJun]

Same here, but I'm not so nostalgic for 8 bit computers.

The only one I kept is the Amstrad CPC6128.

My second favorite machine is the STE.

[rubber_jonnie]

Same here, but I'm not so nostalgic for 8 bit computers.

The only one I kept is the Amstrad CPC6128.

My second favorite machine is the STE.

I have all the 8 bit machines that were a part of my early life, plus the 16 bit ones too (Then there are the others :) )

[rubber_jonnie]

OK, so I got to do the Incognito upgrade after work :)

In terms of the upgrade, it isn't too hard, but there is a lot to disassemble, the 800 is built out of tanks and granite!! I won't go too far into the teardown as it's standard stuff and I want to focus more on where things are wired up to, as there is some soldering required.

First off there are a couple of bodge wires required, one on top of the mainboard, one on the bottom. I used red wire to give a good contrast in case I needed to backtrack:

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Next I made sure that the 6 wire plug had the wires laid out as follows, the silver dot marking pin 1:

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The reason I did this was that I was following an online guide (Installation instructions.) that used this colour code. I had to switch some of the wires round in the plug, but it was simple to do.

Next I replaced RD4 and RD5 with 2.2k 1/4w resistors as suggested:

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This is a suggestion by Flash Jazz Cat in his Incognito install videos.

Next step was to start soldering in the wiring harness to these points:

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These four (Red, white black & blue) are on the mainboard and easy to find, the black and blue being to the resistors you just swapped out :)

The yellow and green go to the CPU board, and connect to pins 9 and 15 of the Antic chip:

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Note there is also a ribbon cable that goes from the IC just behind the incognito card (You need to remove it) to the other side of the card. Note that all of the cards have their IC's facing the back of the machine:

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With that the wiring was done and I connected everything up, the wiring harness to the 6 pin connector as follows:

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I powered it on, et voila!!

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Next step was reassembly, and the only thing I'd mention is that the ribbon cable is quite short and won't go over the top of the Incognito. I ended up filing a slot at the left end of the Incognito slot to allow the ribbon cable and 6 pin connector through as can be seen here:

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And here, with the connections to the CPU board visible:

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And I used some dabs of hot glue to be sure the cables were secure.

After that it's just a case of reassembling the faraday cage and casework and you're good to go.

Next up I need to prep my CF card, so all I need to do is revisit what I did with my SIDE3 cart, If I can remember what that actually was...

There is another mod that adds a button to allow drive swapping, and I may do that later, but for now the possibility of backfeeding the FPGA with 5v and killing it put me off just a little...

[HigashiJun]

Well done !

:bravo:

[rubber_jonnie]

Well done !

:bravo:

Thanks. I started playing round with partitions earlier but need to come to bed, something for tomorrow or the weekend.