Ksarul

The modification to the card gives the HDX software greater capabilities--and it is definitely a worthwhile mod.

OK, YLOAD is the assembly loader that is used to load the Assembly programs. LOAD is the XB program that starts everything. Each of the other programs on the disk is in Assembly--and will not load directly into Extended BASIC. You'll get the I/O Error 50. From the looks of things, since only the first two selections are showing up in the menu, there is something wrong with the XB part of the loader. There may also be a problem with your expansion memory--as you need it to run any Assembly program. Since you do have a 32K card--the problem may also be with your card, probably in the low memory area, as that is where YLOAD gets loaded by the CALL INIT:: CALL LOAD("DSK1.YLOAD"). That should be loading to the low memory while the menu is being built, and if it fails there, either YLOAD isn't loading (possibly a corrupt file), or the memory it is trying to load into isn't there (Low memory on the 32K card) or possibly just partially functional. It is also remotely possible you have a bad Extended BASIC cartridge (or it has dirty contacts--try and clean them and the cartridge port too), as I have occasionally seen this problem with the cartridge (it is VERY rare though, so the other items are much more likely). You might also want to move the 32K card into another PEB slot, just in case some of the contacts there have been oxidized or gone bad in the slot you're using. . . Thank you for a perfect display of your problem with the video--it was a major assist when looking at the problem remotely!

If you have an RS-232 card in your PEB, look for the TI Starter disk drom !dano! on eBay. Here's a link to his last listing for one. http://www.ebay.com/itm/201079176909? If you ask, he'll probably put another one up for you. He's also here on AtariAge. Some notes on disk drives: your TI controller is for Single-Sided, Single Density disks (it also works with double-sided drives to double capacity). These are 40-track disks, but there is a modification to allow it to use 80-track drives, doubling capacity again. The only way to use 3.5-inch disks is with the 80-track modification (or use a Myarc disk controller, which is a bit expensive when it does come up for sale--and it also does double-density, which doubles capacity again, giving up to 720K on an 80-track disk). Making disks on the PC--make sure you use a 360K drive, not a 1.2M drive, as the TI won't be able to read/write to the 1.2M disks, even if they are formatted at the lower density. You can use any 3.5-inch drive you want--as long as the disks are formatted to the right density for your controller (single density for the TI controller, double density for Myarc). Not all PCs can format single density, so that one can be a crapshoot. . . PM me if you need an Extended BASIC cartridge--I have a LOT of them, and my price is reasonable (If you want the manual too, they cost more, mainly due to the increased shipping cost).

This is not a trivial experiment. There is a way to put the XB functionality into the console--but it requires something called a Zeno Board (and I haven't seen one of those available for sale in a long time, although I do have one for one of my systems). The cartridge has five chips in it that you will not be able to get anywhere else (the GROMs) and two ROM chips. GROMs are specialized ROMs that you cannot replace with a standard EPROM, as the chip has an auto-incrementing 13-bit address register in it. Your computer talks to it as if it were a device, not as memory, per se. It increments and presents the next byte of data on the data bus when selected (although all 8 GROMs in the system advance in lock step and only the one selected presents data). Look at the 512K cartridge threads in the TI Programming subforum and you will get lots of info on how this works amd what current projects are afoot that simulate those GROMs successfully. BTW, there are new cartridge boards out there too--ones that have the capability to emulate an Extended BASIC cartridge and a lot more. I designed the hardware, Tursi designed the software, and Acadiel did most of the hardware testing. I've also got ROM-only boards with space for up to 512K of code--and there are a lot of ROM-only cartridges that it can be used for. I'll be working on soldering the basic components onto a bunch of each of these board types after I finish up here. . .I don't have an EPROM burner set up though, so others have to get chips and do the chip programming on them (the GROM board uses a 512K PLCC Flash chip and an ATMEL ATMega1284P, while the ROM board uses any DIP EPROM from 8Kx8 to 512Kx8.

Or you could just identify the issues and leave them alone, Lee--but describe them (and any known workarounds) in a special appendix of the manual. That way, the rare 99/4 user will know exactly what things to avoid doing from the get go. . .and won't have expectations of programming perfection.

Rich, BASIC is showing up because it is part of the regular TI menu. The cartridge image doesn't have any GROM in it, so all of the useful GPL tricks won't work to get the menu up all the time. We are at the mercy of the 74LS378 here--and its initialization state. Usually, all of the chips from the same vendor initialize the same way, but there are no guarantees, as the initialization state is not specified in the specs. That was one reason we tried the GAL (which failed for reasons we haven't run to ground yet), as we could guarantee the initialization state with it--and switch it between inverted and non-inverted bank switching mode with a single jumper. If we ever do work out the GAL issue, I'll make some more boards designed to use it, but for now, it is a dead end.

The 99/8 mobo has finally slowed down a little, it is over $600 though, which is really high for what the buyer is going to get out of it. . .

Michael, I'm pretty sure that Michael Becker owned one of each of those at one point in time. I know he brought one of them to one of the TI Treffs that I was at. . .I think it was the 99/5. I won't be able to bring a Hex-Bus floppy, as I won't be able to come to Birkenau, unfortunately. Doesn't Ciro have one?

Depending on the loader--it might be trying to load Extended BASIC stuff, or it might be trying to load Assembly programs. I suspect the latter, as the error seems to fit. Look to see if your loader program has the commands CALL INIT :: CALL LOAD(DSK1.PROGNAME) somewhere in it, where progname will be the name of one of the files on your disk (the actual Assembly loader).

The 4 has the full 16K of VRAM--but the VDP doesn't have all of the features of the 9918A (I'd have to check the manual to be sure what they are, as I don't have those differences in my head at the moment).

In the molds, I just stick a metal pin in the screw holes to keep them clear. That also helps on removal from the mold, as the pin can come out with the case if it gets stuck. . .and getting a high-quality Shapeways print as a template is a good idea. Let me know once you've verified the minor issues in the current STL files and I'll get one made that way.

Was that with one of the boards I sent you recently or was it one of the ÜberGROM boards? The case looks nice with the three screws. I should probably get one of those from you to make a mold set using it--then I can make some really nice impact-resistant cartridges based on the pattern. . .

I am now the owner of one of the machines that he shows on that page--S/N 80. I also have one of the last ones completed--SN 103 on the case but SN 134 inside. Both of them have the Pascal GROMs and ROM, but it isn't working on one of them. I also have a pair of 128K cards and a 512K card for them (along with the necessary Armadillo Interfaces). Lastly, I have an RS-232 card with a DSR designed for the /8.

Nice work. I like it!

Note, the 9118 VDP, all four of the specialized chips (OSO, POLLO, MOFETTA, and AMIGO) are missing, the RAM is not present, and none of the daughter boards are installed (Pascal, Extended BASIC, and the start menu boot ROM board). I have three or four partially assembled motherboards for the 99/8, and all of them are more complete than this one is.

It does. The ball is one of the really nice pool cue ball types too--not one of the cheaper plastics.

That's actually the original price for one. . .I have had one since they first came out. I used it to play Centipede, for the most part.

The connectors on your cables are no longer available anywhere (unless someone still has a few in the back corner of a warehouse somewhere). IEC used them for their TI cables until they ran out of them five or six years ago (I bought a couple of cables from them back then and some had the nice male connectors on one end and some were like Arcadeshopper's cable). I think they may still have some of those cables for the cartridge port. The other thing to note about the cables using that brand is that you can't mix them with other brand connectors, as they reverse the even and odd wires on the cable when compares to how they come out using other brands. Use two of the same brand and it works fine--mix them and you have cable salad. . .

Good advice so far. It also looks like some of the signaling on the Flex Cable card is getting through to the PEB bus, as it is doing a fast poll of the Disk system. Since that is the first poll on the bus, the problem is most likely one of the other cards (as the disk controller and Flex Cable seem to be working). Not a guarantee, but a definite good place to start. One other note--sometimes a PEB slot gets worn contacts or gummy, so try the cards in another slot--it doesn't reall matter where in the PEB thery are, with the exception of the disk controller, and that only has to be at the end because of the cables, so you can stick it in the second-last slot too.

I had a lot of fun trying this one. Many thanks, Lucien!

No problem, Michael. I'm just happy you've got the 99/8 working in MESS. . .and thanks for all the work you do with the Geneve and the 99/4 series stuff too. Is anyone still working on the Tomy Tutor/Pyuuta to keep it up to date/running? I have pretty much everything made for those systems. . .although much of the text is in Japanese.

They will NOT do anything useful. Two 32K cards probably won't cause the system to crash--but they give you nothing over what a single card will, as they occupy the same place in the TI memory map.

Thanks! I hadn't seen one of these before.

It is up on WHT witht he other 99/8 documentation, Michael. Here's a link to the document: http://ftp.whtech.com/datasheets%20and%20manuals/99-8%20Computer/TI-99_8%20Mapper%20Specifications%2003-23-1983.pdf Look at pages 3-5 and 3-6 for the equations, and at pages 3-8 and 3-9 for the AMIGO pinout. Look at this document to understand exactly how the AMIGO registers work: http://ftp.whtech.com/datasheets%20and%20manuals/99-8%20Computer/TI-99_8%20The%20Mapper%20And%20Us%2005-26-1982.pdf

Obviously, this guy has found the stuff for the 99/8 that I put online, as he references some of the notes I gave to Kyle Crichton about the possibility of reconstructing the special purpose chips. The only one that would give trouble reconstructing would be the AMIGO, as I have the equations for the portions that work like a PAL, and I have a description of the operation of the registers that make up the rest of the chip, but not their exact internal arrangement. It would require a bit of minor experimentation, but it should be able to be reconstructed with a bit of perseverance. The other chips would be easy, as the drawings I put up for OSO, POLLO, and MOFETTA went right down to the gate level. The HOMBRE diagram that I put up at the same time was for the reduced parts count /4B, not the 99/8.