nama

I think I've found an error already. Pretty sure CR203 on the analog board is connected to +12V not +5V. Thanks for the heads up!

Haven't looked at it in any detail, but I think this will be perfect. Thanks River Patroller and Jerzy Sobola.

I'm looking for a clean scan for the Atari 810 analog board schematic. There is a very very bad scan in the service manual v2, but it's unreadable. Any help would be greatly appreciated as I've been battling with drive for weeks (months?). Had it working at one point, but after reassembly it stopped again!!!! bloody crappy old stuff!!!!! Thanks in advance

Not sure if this was mentioned before, but please use a more standard ROMs. The masked ROMs Atari used are a pain in terms of finding replacements or making adaptors. I'm sure you're doing this already though.

Hi, Here is an update. After applying a bit of pressure to the pressure arm I was able to get the drive to load a game! I thought I would do the pressure fix as described in the field manual. After doing this I wasn;'t able to load anything...bummer ? after much fussing around I was only once able to load the games menu as before. So not sure why I made things worse. But at least I still know the basic function of the drive is still working. I guess there may still be a pressure issue, but also likely an alignment issue. I have made myself an 810 diagnostics cart and will use that to attempt to perform a alignment test/fix. It took some searching to find that the probe points on the upgraded 810 drives are TP2 and TP3 on the drive analog board (for your future reference).

Hi all, Over the weekend I was able to get my 810 drive partially working. I replace the RIOT (which tested dead in my 2600) and burnt a new (E)PROM. Previously the drive would spin endlessly and the head would never move as it should. After the fix the drive would spin then stop and the head would do its usual movement. However all my disks would not boot (I suspect many are the wrong density) except one. The floppy that worked is a multi games disk, and I was able to boot to the games menu, but not able to actually load any games from there. I suspected the drive speed so I tweaked it using some drive speed software to be exactly 288rpm. After I did that now nothing loads!!!! Weird! Head is clean. and I get a lot of knocking as the head hits track 0. Wondering if anyone has any insights. Alignment??? Thanks

Thanks guys, I should have mentioned that the machine looks to have the 64k mod done to it. I have done as you suggested and swapped out as many of the 'big' ICs from my 800xl into the 600xl and I could not find any bad ICs. I could not however swap the OS Rom, BASIC ROM and the 6520 as those are soldered in on the 800xl. Anyway, I keep coming back to the BASIC ROM... Removing the BASIC rom altogether doesn't change the behaviour of the machine (boot to black screen, but can run SALT and Defender from cart). I also noticed a cut trace. In the picture attached the bottom trace is intact, the top trace is broken. The top trace used to go to pin 18 on the BASIC ROM. I have tried jumping it, but no change. I have searched hard for anything about cutting this trace or images of 600xl motherboards and can't find anything about this. To me it looks intentional. Cheers again

I recently got a 600XL and on power I am greeted by a BLACK screen. I was able to install my SALT cart and it booted, and told me ROM error (but not sure if I can believe that), and RAM is all ok. Coincidentally most other cars don't work except Defender that seem to run perfectly!!!! Symptoms and observation: - Black screen (with brief red flash) - Keyboard dead. Have been using the one from my 800xl for testing - Holding option does nothing at power-up. Does no go to Self test. - Have tried some other carts. The Defender Cart seems to run ok. Not tested much beyond that. Things I have done. Tried to make a 2764 to 2364 adaptor and replace the BASIC ROM. Not sure if the adaptor is right, and it didn't change anything. Burnt a 27128 to replace the OS ROM...that didn't work either, and in fact seemed to make things worse. Maybe I burnt the wrong .bin file. Thats about it. Any help or recommendations are VERY welcome. Thanks

Ok, last night I swapped in a 2732 burnt with the archiver ROM image and followed the instructions in the Archiver/Chip manual for install. No change. Endless spinning drive. I then burnt the standard 810 (Rev-C I believe) image to a 2716 and wired that up with instruction found in these forums...that also didn't work. Endless spinning. So maybe the original ROM is fine(?), and my next port of call is changing out the RAM...I have some on order. If that fails I'll have to start from scratch, and be 'lost' all over again ?

Oh...apologies. I thought it was you.

Thanks! Can I ask what component you replaced that allowed your 810 to initially "get past POST" ? Tonight I'm going to burn a 2732 EPROM with the Archiver image and install that (with the appropriate mods). Fingers crossed that will fix it.

Hello again. I've tested my 810's RIOT and the CPU by swapping them into an Atari 2600. They work fine. So this leaves me with the RAM and ROM next to test. Can I ask what component you replaced that allowed your 810 to "get past POST" ? Thanks

Unfortunately not at the moment. If I'm lucky, I may be able to get a 1050 in a month or two.

I recently go a 810 that is the always on busy light, and constant spinning mech...following this thread with anticipation.

Hi Simius, are these still available?

Didn't realise that was there!

Thanks, I appreciate your advice. Yes, I'm not a member of a C64 forum (should be I guess). But thought someone here would certainly know.

Does anyone know if I can use this C64 Power Saver with my Vic20 (NOT 2 pronged power version). https://www.pcbway.com/project/shareproject/W217819ASN17_C64_Power_Saver.html Thanks

I just ordered one of these and it should be here (NZ) in a few of days. I've heard they are quite thick and may need filing down so they can sit a bit more flush with the case, as per the original.

Just bumping this up a bit. Still hoping some generous person can help me out. Thanks!!!!

As hueyjones70 mentioned. If I first test the memory with 'BYE' then reset out, and then press 'OPTION' it seems to work...go figure????

I spent a few hours on the weekend restoring this machine, one thing I did was to completely strip back the keyboard and give it a very good clean. All keys are very responsive. I don't think it's been taken apart before, so I'm assuming the ROM is original.

Mine does the same. The OPTION key works fine. Typing BYE works fine, and the computer seems to have no issues. Just won't boot into test mode when pushing OPTION. Weird. Looking forward to the replies.

Hi All, Was repairing an Atari 800XL over the weekend (came out fully functional, and looking very nice!), and found I need 2 conical keyboard springs. The ones in the machine have been destroyed :-( I have the Mitsumi keyboard variant. Just wondering if someone here may have a couple of springs they could spare. Thanks & cheers Philip

Found this. Wile this work?: https://www.supercheapauto.co.nz/p/dupli-color-dupli-color-metalcast-aerosol-paint---enamel-grey-metalic-ground-coat-311g/105534.html#q=Anodised%2Bpaint&lang=en_NZ&start=8