Ksarul

Thanks for the update, Sparky! It is good to see you back--and may the mending trend continue.

Note that he identifies two other eBay accounts (brothers) also selling items from his father's collection. . .so it is actually more than just what's up there on his page.

Boulder Dash by Eric LaFortune and commercially released by Legio Computer required the Mini Memory. The US version was renamed Rock Runner, loaded from the Editor Assembler, and was released by Asgard. Mini-Pede by CSI Design. Chosen for release by TI, but production never started and so CSI released it under their own name. Entrapment was also intended for the Mini Memory. It was almost to release when TI pulled out of the market, so close that they actually had a large number of tapes already made. Those tapes made it out into user hands via random lots of tapes (in groups of six) that either Tenex or Triton was selling for an extremely low price. I bought three or four lots to see what would be in there and found two copies of the Entrapment tape in them. I gave one to a friend, but I still have the other somewhere in my collection.

Testing with a second controller will definitely help. . .

I have generally had fun with this game--it is one of a very small number of TI games that I actually don't have to worry about my general lack of fine motor control on. . .stable soldering iron: yes; stable motion control: not happening.

On the floppy controller, the only thing between PIN 26 and the TR00* input of the chip is a 3.3KOhm SIP resistor with +5V on the other side. Here's the CorComp Schematic for the 2793 board.

I have definitely verified that it is an 18-pin Intel chip, but no luck yet on getting a datasheet. Next stop on my hunt would be a 1980s Intel databook.

A 2889 is an 8-pin isolator chip and a 2446 is a 50mV shunt. How many pins is the chip on your board showing and what is it connected to? Beware of some early lots of 2793 Floppy controller chips too. A whole bunch of 1984/1985 date code ranges came bad out of the factory. Later chips weren't problematic (or earlier ones, for that matter), but a lot of companies got burned by the bad ones BITD. CorComp actually redesigned their floppy controller away from that chip after they received a lot of 500 of them for their initial production run and found out most of the chips in the lot were bad. They put a 1773 in its place using a small daughter board socket to avoid scrapping the whole board run. Finding many poorly photocopied, hand-drawn schematics over the years is exactly why I started the documentation preservation project for such things.

I like this so far!

Which floppy controller was it using? This could be interesting. . . Is it possible to scan the old schematics? I try to take the ones that are HTF and convert them to Visio to make them somewhat more accessible to the community. I've done quite a few (all posted in one of the documentation threads here on AtariAge), with more to come as I get time to work on them. One of the ones in the repository already is for the Quest 200 board. . .I actually have permission to make more of those (and have a few prototypes that I still need to build/test).

On the disk drives--are the proper drive selection bridges in place and is the last disk in the chain properly terminated? These things can also cause problems if not right. . .

Michael Kürbis hat damals vieles an Hardware gemacht. Ich habe damals beim Regionaltreff sein TI PC Tastatur Karte für die Peri Box ausgetestet. . . And for the English-speaking crowd: Michael Kürbis made a lot of hardware back then. I had an opportunity at a regional TI meeting to play with his TI-PC Keyboard Card for the PEB. . .

Looks like the link goes to dead space, unfortunately. . .as does the path on Wordpress.

Rochester Electronics has both of them in both DIP and Surface Mount--in vast quantities. Minimum buys are a few hundred each though. . .

Cosmopoly is a different game with the same general concept. Here is the Cosmopoly manual. I thought I had it, and was able to locate it this afternoon. Now back to testing SAMS cards. . . Cosmopoly_0001.pdf

I do have a 512K board that Marc Hull and I designed that works like a standard 378 (non-inverted) Red board, but which always starts in Bank 0. We used it for the Tex Turbo cartridges.

1.5 stop bits were indeed intended for use with old-school teletypes, but oddly enough, that was only the nearest possible approximation of the teletype's intended number of stop bits: 1.42. That value gave the mechanical parts of the teletype just enough time to come to a readiness standstill (quiescence) for it to be ready to accept the next character. That also allowed it to work just a "touch" faster than it would have if they'd rounded up to 1.5 bits at a time when 45.5 BAUD was a normal line speed. I used to work on those beasties BITD. . .

And now I have yet another Berlin group making music to hunt down. . .I like it.

I think I've seen that name in one of the Facebook groups. With luck, he may still be there to ask about the side B programs. . .

Will the FD55F drives work? Yes, with a really big caveat: the drive controller does not know to double-step the heads, so it only sees the first 40 tracks on each side of the disk. Why is this datum important? the disk will work fine in any 80-track drive with your CorComp, but it will not even be readable in a 40-track drive, as that drive will only see 20 formatted tracks per side. It "may" be possible to set the drive to automatically double-step, but you would have to read the technical manual for the FD55F drive to see if that is a possibility. On a side note, when used in a Geneve9640, your CorComp controller will actually be able to format and use 80-track drives, so you could get the full 720K formatted capacity the drives are capable of. It would also have issues reading the normal 40-track disks, for the same stepping issue identified above. The controller does not know it needs to double-step, as the firmware in the CorComp expects a 40-track drive.

Black boards have between 8K and 128K chips on them, for a maximum of 16 banks in inverted mode. Red boards have between 8K and 512K chips on them, for a maximum of 64 non-inverted banks. Yellow boards have chips between 512K and 2M, for a maximum of 256 non-inverted banks. Note that there are 128K and 256K chips in the correct 40-pin form factor for a Yellow board, but they generally cost more than their 32-pin counterparts (used on Black or Red boards) and so it makes little or no sense to use them most of the time. UberGROM boards use PLCC ROM chips from 128K to 512K, and so have a maximum of 64 non-inverted banks, like the Red boards.

Trying to blenderize the side panels of every car you pass, are you? LOLOL

Answering the original question: the 74LS377, 378, and 379 all start in an indeterminate state, as already noted. However, each chip tends to default to a specific bank on startup, so when I build boards, I verify that the board will always start in the first or last bank. This way, if your header software is in both of those banks, the board "should" always start up properly. Using a single bank of GROM for your loader is definitely a viable solution, as it ignores all of the vagaries of the ROM startup bank, but it does add a complication for physical cartridges: you would need to use an UberGROM or FinalGROM cartridge board to run it. Making it as a permanent UberGROM cartridge would be very interesting, and if you were trying for a good generic solution, the GROM header would always just select >6000 and execute from there. This way, one GPL startup routine would be usable for any cartridge designed to use it. TI did something similar with their ROM-launching GROM (CD4326) as used in Sneggit, Early Logo Learning Fun, Crossfire, and Hopper and Funware did the same with their St. Nick GROM. Both of these examples were designed to force use of GROM, not to set bank-switching addresses, but the basic idea of a GROM controlling a ROM launch is the same.

CorComp 32K RAM, missing the metal clamshell. Running it like that will do no favors to those voltage regulators--they will fry in no time without heat sinks.

Almost all of the preproduction (qualification) labels are in the handwriting of about half a dozen people. This one does not look to match any of them, but I would have to pull some of mine out for comparison to be sure. Generally, the qualification labels are also a very different label style, but there are exceptions, so the label style isn't always a perfect diagnostic. As the cartridges in a qualification run are intended to test the production process, the date stamps on them actually had importance to TI, and so such stamps were generally present. One key is that the production date will be before the production date of any of the regular release cartridges of the same title, generally by about a month (or a little less).