Getting Started Programming the TI-99/4a

[idflyfish]

Hello all,

 

About a year ago I felt the urge to purchase a TI-99/4a. I had one as a kid and used to love playing games and seeing what I could make it do. Over the last year I have managed to add a PEB with a disk controller and disk drive (of course), a memory expansion card, and a program recorder. I have also played around with Win99/4a. I have done quite a bit of reading and I think I am now ready to start coding.

 

I understand that there are utilities to transfer files from emulators running on a PC through a serial port to a TI but those files have to be in TIFILES format. Are the Win99/4a floppy disk files in this format?

[Willsy]

Unfortunately they are not, but they can be converted with some free software called TI99Dir (do a Google for Fred Kaal).

 

It's worth pointing out that Win994A although very nice, is effectively no longer supported by its author. Classic99 is another great emulator (better than Win994A IMHO - ESPCECIALLY if you want to write software) and it natively supports the TIFILES format. Like Win994A, it is completely free, though the author will gladly accept a donation via his web site.

 

See harmlession.com for the download page.

 

Regards

 

Mark

[idflyfish]

Mark,

 

Thanks for the info. I will check out Classic99 after work today.

 

Mike

[matthew180]

Using Classic99 you can forget about the Win994a "disk files" and just use the individual files directly on your PC's hard drive, then transfer those files to the 99/4A via the serial I/O (and MagicFM on the 99/4A side), or via a flash card if you have the CF7 device. For example, Classic99 has 3 directories called DSK1, DSK2, and DSK3, and when you read or write any files to those devices on the 99/4A side, the files go in to their respective directory as *files*, and not some virtual disk wrapper around them. This also means the Classic99 disks are only limited by your PC's hard disk. If you do something like SAVE DSK1.TEST in XB, a file called TEST will show up in the DSK1 directory, and you can *directly* transfer that file to a real 99/4A, load it up in XB and run it.

 

I think there is also another program out there that lets you use your PC's file system as a disk on the 99/4A, but I can't remember the name. It uses the serial port, makes a virtual disk on the 99/4A side, and reads/writes files directly to the hard disk on the PC side.

 

When I need to get files from my PC to a stock 99/4A with the PEB (i.e. NOT using the CF7 device), I use MagicFM which runs on the 99/4A side and basically turns your 99/4A in to a host system that you can connect to with a terminal program and manage files (catalog, delete), and upload / download files via xmodem. Of course there is the chicken and egg problem here in that you need to get MagicFM on to a 99/4A floppy disk before you can use MagicFM to transfer files.

[idflyfish]

Matthew,

 

Thanks for the great info. All of this will come in handy.

[Willsy]

I think there is also another program out there that lets you use your PC's file system as a disk on the 99/4A, but I can't remember the name. It uses the serial port, makes a virtual disk on the 99/4A side, and reads/writes files directly to the hard disk on the PC side.

 

Talking of stuff like this, I just got one of Fred Kaal's HDX modified RS232 cards. Awesome. You run a server on your PC, connect the PC and the TI via RS232/2 and it gives you HDX1 HDX2 and HDX3. Subdirectories etc are supported.

 

Absolutely-frickin-awesome!

 

This is the model that I have.

 

Mark

[idflyfish]

That is very cool. Can you point HDX1 at the DSK1 directory under Classic99? That would be neat.

[matthew180]

Ah yeah, Fred did do that serial-to-PC system! Cool, thanks for digging that up, I'll have to try it! Oh, and thanks Fred!!

[Willsy]

That is very cool. Can you point HDX1 at the DSK1 directory under Classic99? That would be neat.

 

I think you can. I'll try it later today just for kicks.

 

HDX Server persists files in V9T9 format. Although Classic99 considers the V9T9 file format deprecated, it does support V9T9 files. In the latest versions of Classic99 you can set individual DSK folders to use either TIFILE or V9T9 files. This is very handy. I can tell HDX Server to use C:\Classic99\DSK0 as its disk folder, and set up classic99 DSK0 (through the user interface, no need to mess with ini files) to use V9T9 type files for DSK0. Then, you can seamlessly share files between your PC and TI.

 

For example, if you write an XB program, or assembly language #3, or #5 file, *whatever* on the real TI, and save it to HDX1.whatever and it will actually go to Classic99s DSK0 folder in V9T9 format (because that is the format that HDX server uses). You could then load that file in Classic99 no problem at all.

 

Of course, the opposite would also be true. A file created in Classic99 and saved to DSK0 would be written in V9T9 format, automatically in the correct format for HDX Server to work with, so the real 4A, connected to the PC via the serial port could IMMEDIATELY use the file. No translations necessary. The real 4A doesn't even 'know' that the file has come from a PC via the serial port. It's all abstracted away via the DSR.

 

Awesome.

Edited June 24, 2011 by Willsy

[marc.hull]

That is very cool. Can you point HDX1 at the DSK1 directory under Classic99? That would be neat.

 

I think you can. I'll try it later today just for kicks.

 

HDX Server persists files in V9T9 format. Although Classic99 considers the V9T9 file format deprecated, it does support V9T9 files. In the latest versions of Classic99 you can set individual DSK folders to use either TIFILE or V9T9 files. This is very handy. I can tell HDX Server to use C:\Classic99\DSK0 as its disk folder, and set up classic99 DSK0 (through the user interface, no need to mess with ini files) to use V9T9 type files for DSK0. Then, you can seamlessly share files between your PC and TI.

 

For example, if you write an XB program, or assembly language #3, or #5 file, *whatever* on the real TI, and save it to HDX1.whatever and it will actually go to Classic99s DSK0 folder in V9T9 format (because that is the format that HDX server uses). You could then load that file in Classic99 no problem at all.

 

Of course, the opposite would also be true. A file created in Classic99 and saved to DSK0 would be written in V9T9 format, automatically in the correct format for HDX Server to work with, so the real 4A, connected to the PC via the serial port could IMMEDIATELY use the file. No translations necessary. The real 4A doesn't even 'know' that the file has come from a PC via the serial port. It's all abstracted away via the DSR.

 

Awesome.

 

 

 

That looks pretty cool. I never realized that that is what the card was. If I understand correctly...

 

With this card in place, all a person would have to do is "SAVE HDX1.name" or conversely "OLD HDX1.NAME" from a TI and the card and PC will take care of the rest ? If so then this would seem to solve most of the problems encountered with the NANO PEB not playing nice with the PEB.

 

Any idea if Fred's DM2K can utilize the HDX ? And....Does Fred sell these devices and cables ?

Edited June 24, 2011 by marc.hull

[matthew180]

http://members.ziggo.nl/fgkaal/Hardware/hw_ti99hdx.html#ti99hdx

 

There are 4 ways to connect the TI to the PC, one of them uses the standard TI serial card, but is limited in what you can do. Fred made some hardware, but it is one-off and I don't think he is interested in mass producing anything, but all the information is there for anyone who wants to put one together for themselves.

 

It looks like a really nice system, especially the 115.2Kbps version.

[Willsy]

That looks pretty cool. I never realized that that is what the card was. If I understand correctly...

 

Yep, that's what it's for. It turns the PC into a file server. The files are hosted in a directory somewhere on the PCs hard disk (or on an SD card, or USB stick, or whatever).

 

With this card in place, all a person would have to do is "SAVE HDX1.name" or conversely "OLD HDX1.NAME" from a TI and the card and PC will take care of the rest ? If so then this would seem to solve most of the problems encountered with the NANO PEB not playing nice with the PEB.

That's exactly right. As far as the console is concerned, its dealing with a disk drive. It has no idea that the RS232 card is being used. The HDX system covers level 2 and 3 DSR commands. Subdirectories are also supported.

 

Any idea if Fred's DM2K can utilize the HDX ? And....Does Fred sell these devices and cables ?

Yes. DM2K can utilise HDX (HDX is just another device, so you could equally use DSKU but I think DM2K offers some extra facilities

Yes. Fred sells the little boards, and there is full instruction on how to build the boards and modify the RS232 card on Fred's website.

 

There are a number of hardware options. I went for the modified RS232 option. One other option Fred sports is a new, custom PEB card with a 16550 UART on it. It would run at 115,000 baud. Much much faster than a disk drive - probably comparable to a hard disk in speed.

 

Given your recent experience with the SID card, maybe you could put a board together? I'd certainly take one, maybe two!

 

The TI99HDX page is here.

 

Mark

Edited June 24, 2011 by Willsy

[marc.hull]

That looks pretty cool. I never realized that that is what the card was. If I understand correctly...

 

Yep, that's what it's for. It turns the PC into a file server. The files are hosted in a directory somewhere on the PCs hard disk (or on an SD card, or USB stick, or whatever).

 

With this card in place, all a person would have to do is "SAVE HDX1.name" or conversely "OLD HDX1.NAME" from a TI and the card and PC will take care of the rest ? If so then this would seem to solve most of the problems encountered with the NANO PEB not playing nice with the PEB.

That's exactly right. As far as the console is concerned, its dealing with a disk drive. It has no idea that the RS232 card is being used. The HDX system covers level 2 and 3 DSR commands. Subdirectories are also supported.

 

Any idea if Fred's DM2K can utilize the HDX ? And....Does Fred sell these devices and cables ?

Yes. DM2K can utilise HDX (HDX is just another device, so you could equally use DSKU but I think DM2K offers some extra facilities

Yes. Fred sells the little boards, and there is full instruction on how to build the boards and modify the RS232 card on Fred's website.

 

There are a number of hardware options. I went for the modified RS232 option. One other option Fred sports is a new, custom PEB card with a 16550 UART on it. It would run at 115,000 baud. Much much faster than a disk drive - probably comparable to a hard disk in speed.

 

Given your recent experience with the SID card, maybe you could put a board together? I'd certainly take one, maybe two!

 

The TI99HDX page is here.

 

Mark

 

 

 

Hmmmmm... That is really fucking clever.... smart is one thing but clever is on a whole different level. How did this go under the radar for so long ? I will give Fred a ping next week and order one of these up. I don't know about the custom card. I have to get my nuts out of my throat first Do me a favor and start a thread extolling the virtues of this beastie. See if there is any interest.

[Willsy]

Do me a favor and start a thread extolling the virtues of this beastie. See if there is any interest.

You wish is my command... I did a YouTube demo last night. See new thread

[idflyfish]

That is very cool. Can you point HDX1 at the DSK1 directory under Classic99? That would be neat.

 

I think you can. I'll try it later today just for kicks.

 

HDX Server persists files in V9T9 format. Although Classic99 considers the V9T9 file format deprecated, it does support V9T9 files. In the latest versions of Classic99 you can set individual DSK folders to use either TIFILE or V9T9 files. This is very handy. I can tell HDX Server to use C:\Classic99\DSK0 as its disk folder, and set up classic99 DSK0 (through the user interface, no need to mess with ini files) to use V9T9 type files for DSK0. Then, you can seamlessly share files between your PC and TI.

 

For example, if you write an XB program, or assembly language #3, or #5 file, *whatever* on the real TI, and save it to HDX1.whatever and it will actually go to Classic99s DSK0 folder in V9T9 format (because that is the format that HDX server uses). You could then load that file in Classic99 no problem at all.

 

Of course, the opposite would also be true. A file created in Classic99 and saved to DSK0 would be written in V9T9 format, automatically in the correct format for HDX Server to work with, so the real 4A, connected to the PC via the serial port could IMMEDIATELY use the file. No translations necessary. The real 4A doesn't even 'know' that the file has come from a PC via the serial port. It's all abstracted away via the DSR.

 

Awesome.

 

Awesome indeed.