Ksarul

The only other cartridges I've seen that used CRU switching were from DataBioTics (only half a dozen of their titles used this method), and with the exception of the SuperSpace II cartridge, none of those titles included a GROM. Modifying the cartridge port to bring the missing CRU lines up to the connector would be definitely useful to get all of them running, as long as the motherboard wasn't using the V2.2 OS.

A couple of important things to note on 3.5 drives. Using them with a standard TI controller and the original DSR chips, you get data on the first 40 tracks of each side in single density, format (90K per side, 180K per disk). Note that the last 40 tracks of each side of the disk will be completely unused, and this format will not be easily read by other TI equipment. This is caused by the fact that the TI does not know to double-step when formatting a 3.5 disk in 40-track mode, so it single-steps and makes really strange disk geometries. There is a bit of a solution here, in that you can modify the DSR so that it formats 80 tracks per side (modified DSR chips are available from @atrax27407 for a reasonable fee). These disks would now be 180K per side--360K per disk. It is generally better to use 720K drives here, but the 1440K drives will downshift to 720K mode when used with 720K floppies. Note you can't get double-density from a TI controller, but this method of adapting it to use as much of the 720K disk as it can is pretty much compatible with any TI modified to read/write in 80-track mode. Ribbon cables are a bit different. TI controllers don't expect the twist in the cable that is normal for PCs--the TI wants the cable to be straight through. This is yet another reason to use a 720K drive, as most of those actually have drive select jumpers for up to four different drives on a cable (some use 0-3 as the ID on the mask, others use 1-4, but all distill down to the same four electrically identical addresses as far as the computer is concerned), so no modifications to the cable are required. With 1.44M drives, most of them are hardwired to be drive "B" (disk 2), and don't have options to set the drive selection differently. You can build a cable that moves the desired drive select wire in the cable to the disk 2 select position on the drive to get it to respond as a different drive (that's what the twist does for the PC, but it also switches other wires that mess up the TI controller, which is why you need a "mostly" straight through cable at all times).

On Funware carts, they should all work on any non-V2.2 OS set, as they are almost all standard 8K ROM cartridges. One exception is St. Nick, as it will even run on a V2.2 OS set (just like the Parker Brothers cartridges). If you have one that isn't showing up in the menu, it may be a bad ROM, misaligned cartridge board in the slot (a common problem with their boards, as they had a bit too much wiggle), or issues with the cartridge port itself. Since you say all other cartridges work, I would eliminate that last possibility here.

Is your drive the Shugart or the MPI drive? The MPI drive has a whole door that slides open and the drive flings the disk partway out, whereas the Shugart drive just has a (somewhat) wide latch that you open and close to insert/lock down the disk. Note that the MPI drive is belt driven, and those belts get old and loose. . .

I have both editions of the Koppelmann book. Both are pretty HTF, as he only printed 150 of the first revision and 47 of the second. I bought my second edition copy directly from him at one of the TI Treffs, and my copies of Assembler Kurs II and III directly from Hagera. The IUC also has a few other German books scanned in, along with a small number of German magazines.

Here's the Assemblerkurs II scan, and just in case, here's the Assemblerkurs III scan. It doesn't look like the Koppelmann book is online in either edition yet. The IUC site has a lot of the books released in other languages on their site, so it is usually where I go first to check for book scans in other languages. I have the books for the most part, but scans are good to have too.

There are at least two variants in the wild using 2793 chips, and two more using the 1773 chips, so that would definitely result in a total of four versions of the board. You could count a potential fifth variant, the 1793 board with the 1773 daughter board on it. . .

This is a somewhat regular modification to Rev C CorComp boards. Here's a picture of another one, also modded extensively.

There are several answers to your question: @atrax27407 can provide a functional set of the EPROMs for a reasonable fee, there are appropriate BIN files out in the wild that you can burn into an EPROM yourself (assuming you have the equipment to burn TMS2532 chips), and I believe @arcadeshopper also has a service to replace them (also for a fee, but he is then doing the replacement for you if you don't do soldering yourself). In all cases, it is a really good idea to put the replacement chips in sockets, as that makes future troubleshooting a bit easier.

It looks like the disk controller card is being successfully selected, but the follow-on activities are not registering. This could be a ROM issue, but there are a number of other chips involved in that power-up sequence as well. I personally usually start by looking at the 74LS244 (there are 3 of them) and 74LS245 (only one of these) chips, as they are integral to the buss communications, but this one could just as easily be a blown DSR EPROM. A lot of folks move the disk controller card into the seventh slot to get better access to the disk drive cable, which is a really good solution if you are not using all of the slots in the PEB. The card address is actually on the card in TI systems--the buss does not care where individual cards are inserted (unlike older Apple machines where the slot is critical for certain functions).

I use one that is a bit of a beast, although I got one for quite a bit less than they seem to be going for now.

Not a special edition at all. TI made four separate variants of their Joysticks, three of which use the same form factor as the set you picture here. These were the first of the three types using the form factor, with them switching to the orange button on a black base about a year later. Prototypes exist of the last form, which had purple fire buttons and a beige case like the later consoles did. Only the beige variant is rare (I know of about a dozen or so sets of them in the wild, one of which is part of my collection). The black button style is not as common as the orange button type, but you can turn up both of them relatively easily on eBay. The fourth joystick type is very different from these, and relatively uncommon even though it is the original TI joystick. These are the true TI Pain Sticks, as the ball at the top will start eating into the flesh of your hand after 20 minutes or so of use (painful experience speaking here from playing TI Invaders with them as a young man). Here is a link to a site with pictures of all three variants other than yours.

This one is actually a very recent port from Inufuto. He's done something like 14 of them for the TI now.

He's smokin' it. . .

Here is a quick translation of the two paragraphs that discuss the ROM and GROM selection circuitry. Note that the pins you are looking at here are not normally used unless trying to decode the ROM space into 2K chunks. . . Martin Board.odt

The Navarone problem comes with how the expander itself works. It only cuts the +5V line to disable the cartridge. There is a whole discussion from an attempt by @Sinphaltimus to make a cartridge expander that would work to isolate each installed cartridge more fully and eliminate the problem. That project never did find a successful end. . .

The boards are just a flat band cable attached to a connector that fits behind the cartridge door. None of the cartridges ever made it into the wild, so far as I know. Several folks have posted pictures of the inside of these early Speech Synthesizers. There are at least two variants of the cable, so not all of them will look alike. I believe Ciro has posted pictures of his, as has Klaus. A few more of us have one. They are definitely not all that common, as the number of consoles in circulation at the time these were made was really low, and uptake on them wasn't all that fast either as there wasn't a lot of early software taking advantage of them.

About the only adapters I've seen with nice pins for insertion into machine sockets are the ones from Aries. I have several different sizes of them that I use regularly. They also seem to be a bit more robust than the others when it comes to the blades that hold the chips to be programmed in place.

Pretty much what TI did with their original boxes. I still use several of them for my primary system boxes during moves. They've moved a lot too--and they have made two round trips across the Atlantic. . .without damage to their contents.

That's a good start on sources of GPL information, but another possible suggestion would be to look at the GPL source code available for several other TI cartridges as well (a lot of it is linked in the resources thread). Every one of them includes a neat new trick or three to wring just a bit more out of GPL.

Only "to" the wall? You got off easy. Most dogs would have fun pulling it "through" the wall to get their daily exercise chasing it around the yard as it slowly disintegrated. . .

Step one done, now comes the hard part. I hope this part works out with a minimum of disruption in your life, @RickyDean.

Progress!

You might also try moving the copper on the cartridge port edge connector back 10-15 thousandths of an inch. They don't like it when things go right to the edge of the board. . . Another suggestion is to bevel the corners of that card edge connector just a bit, as it will go into the cartridge port a lot more easily that way.

Yes, this mod changed the VDP to a 9928. There are several 9928 conversion projects that showed up in various newsletters, and the output from any of them would work with this RGB Interface if routed to the right pins on a DIN6 console connector.