kheller2

Maybe the 64K RAM cards were hybrid Z80/RAM cards... However, the ceramic 40pin in this pictures is very confusing.

Note to self: eBay has an actual 83S DA 000231 113 unit vs the Pilot 83S DA000231 (432)

Is it even possible to redo pokey on a single modern programmable chip? Even PokeyMax required ancillary chips to do pot charges, etc. I think we should just all start wire wrapping this: http://www.retroclinic.com/leopardcats/bbpokey/breadboard_pokey_project.htm

Saw this on eBay. I see a cable, and didn’t known they branded the computer too. https://www.ebay.com/itm/134885134520

Atari 1500XL. XLT for tower, XLC for compact.

Can it actually read a disk (dirty head)?

2600s aren’t in short supply. Nor 850s. Or 1050s. 🤣

Or just use an Indus GT drive for CPM. I’d rather like to see the SPC card done. But that’s another dead “useless” device.

This was the link: http://www.atarimuseum.com/computers/8bits/xl/xlperipherals/1090/Z80 Board/AtariCPM-disks.zip

The MacOS info says it was downloaded via a direct link to the atarimuseum from a post on facebook that Curt did. Probably when he was trying to get SweetPea working. Update, found the post on FB. BTW, FB also had pics of the 1060 sweat pea system from 1986 with Atari CORP markings. Atari Museum Curt Vendel · November 8, 2019 · Hi.. I'm looking for some help. I have Data General MV4000 Restores from Atari HCD mainframe from 1984. There are two Atari CP/M disk directories. I need someone to help me make some Atari format bootable diskettes. Judging by the dates of May/June 1984, these would most likely be the boot disks for the Atari 1066 CP/M cards for the Atari 1090 Expansion box. I'm posting up a link to the ZIP file with the 2 directories, if someone is willing to delve into these and make me some ATR's that I could put onto some physical disks to attempt to get the 1066 CP/M card to boot, that would be fantastic and I will post a credit to you on the Atari 1066 page. thanks.

I'm not sure what this is then. It was from the 1090 section. AtariCPM-disks.zip

Remember that there are two CPM source disks that were released by the Museum, that I think were for the stand alone device, but might be useful for the 1090.

You just need a RCA to COAX adapter and screw it right into the TV. https://www.amazon.com/VCE-Adapter-Connector-Coaxial-Commodore/dp/B08BYD8GV4

I tend to get confused between SALT and SUPER SALT, and which ones require the external test box of which there are several versions.

https://www.ebay.com/itm/166608452500 That looks like type 4 but the keys look shiny and concave. Any ideas or is it just the light?

The 64K cards look the same to my blurry eyes. The difference is one has a ceramic chip and axial vs radial caps. Although I do wonder why there is a VLSI chip on every one of those boards. I’ll see if I have any better pictures from actual samples.

Interesting. The Cherry keycaps are supposedly B-Key colors according to this thread:

HAH, which one should be disassembled? There are so many. What do most people use here?

On my version of chrome, it does download the file as "unconfirmed 13241243145.crdownload". it just doesn't let chrome see it. But its in the downloads folder.

I often thought of hacking a test ROM to do just that: signal different failures. However, the time it takes to burn the code, install it in the box (oh you have a ROM and want to install an EPROM, well, time to move jumpers on the board) and have it tell you its one of the other 3 chips (CPU better work, otherwise the ROM isn't gonna work), is about the same time as just swapping the chips into a working drive to see what failed. Always make sure you have a working system to compare with when repairing/rebuilding. As for why Atari didn't do it, there ain't much room left in that ROM for anything. It's full of diagnostic test code.

Some of Chrome issues might be policy your place of work is enforcing: "Your browser is managed by your organization ". Chrome on MacOS throws up the dangerous download/blocked message for me at the office. Safari happily downloads it. In chrome do this: Settings -> Privacy and security -> Security -> No Protection

Keep in mind that Atari never released official source code for the 1050 and what we have was reversed engineered by several contributors. Having said that, I can't remember if FLOPOS has bugs in it or not. There is a large thread here where we went through most of the code: http://atariage.com/forums/topic/156462-1050-roms/?p=3581549 I would recommend using the enclosed code to examine. I'm not 100% sure about the BIT assignments for PORT B as there is conflicting information. I think I took what I found on the schematics and from Alitirra to adjust some of the notes. This will compile into Revision L (the only difference from K is support for the 2797 FDC). In your snippet, when a "BRK" is called inside the code it hits the special section towards the end called "BREAK" which then jumps to TFAIL. flopsL2.asm

Which picture has it backwards?

It doesn’t require realignment. It requires adjustments on the main board. There is a thread about it.

Quickly scanning the 1050 source code for a stock machine, I think this is the check order: Test PORT A RIOT Test PORT B RIOT Is FDC Ready Test Sector and Track Registers in FDC Head Step In ROM Checksum RAM Test 6810 If that is the right order, and you don't see a head movement, that sort of implies the RIOT is shot (or the FDC). (Interesting how they test the RAM after they do a ROM computation using the RAM for summation).