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fabrice montupet

99/5 TI documents Quest

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My doubts were focused on the 256 bytes of on-chip RAM but I have absolutely no certitude.

 

With the memos in hand it should be easy to test which of the proposed changes were adopted (if any):

- "Move of internal CRU bits from >1EE0 to >FEE0". From that base address CRU bits >5 through >F are user bits that can be freely (re)set and read back. This is the easiest test.

- "Move internal RAM from >F000 to >FF00". As code in the internal RAM runs much faster than code in regular RAM this should be easy to test: run a 1,000,000 times loop (assembly) at both addresses and see which one is the fastest of the two.

- "Lengthen /DBIN to match /MEMEN". This can be tested with putting the CPU in a tight loop ('LOOP JMP LOOP') and looking at /DBIN and /MEMEN with a logic analyser or two channel scope. If the negative flank of both signals occurs at the same time, the modification was made.

Is it possible to perform those tests? I think the first two might have been done, the third seems more unlikely to me.

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According to the (GREAT) document that you have provided, my pre-feelings on the internal ram appears to have been founded.

Confirmation (or not) about an internal RAM modification very soon, I will do these tests this week-end.

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According to the (GREAT) document that you have provided, my pre-feelings on the internal ram appears to have been founded.

Confirmation (or not) about an internal RAM modification very soon, I will do these tests this week-end.

Fabrice,

 

Did you find the time to perform this test? I'd be very interested to hear confirmed that indeed a modified 9995 was created for the ti99/5.

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I had many things to do these last days (and I went on vacation too) So I have not yet written the assembly program to do a loop test (and even more) in the address >FF00. But I will :-)
It will remind me good souvenirs, I haven't touched to 9900 assembly language since some years.

 

Just for eyes pleasure, here is a picture I drew of the beast some time ago, but I had not yet published:

http://www.ti99.com/geneve/index.php?fr/article35/le-tms-9995-chez-texas-instruments

 

 

 

Edited by fabrice montupet
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I had many things to do these last days (and I went on vacation too) So I have not yet written the assembly program to do a loop test (and even more) in the address >FF00. But I will :-)

It will remind me good souvenirs, I haven't touched to 9900 assembly language since some years.

 

Just for eyes pleasure, here is a picture I drew of the beast some time ago, but I had not yet published:

http://www.ti99.com/geneve/index.php?fr/article35/le-tms-9995-chez-texas-instruments

 

 

 

Hi Fabrice,

 

Did you have time to do those little tests on the 99/5? I'd be really interested to know whether there is a prototype 9500 chip in there, or a plain 9995 as a placeholder...

Many thanks in advance!

 

Paul

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Hi,

Some news about my 99/5 prototype: I dumped its CPU ROM :)
It remains to do the same for the GROMs. It's a little less easy because the existing tools to dump these memories crash on the 99/5.
I tell you more soon!

Edited by fabrice montupet
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very cool! congrats!

you could try the memory editor that comes with the Gram Kracker to see the Grom Content (+dump option), the editor is completely independent from System Rom/Groms.

So if the Grom port has the same address in CPU memory as the 99/4a, it should work.

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Thank you!

 

Thanks to Michael Zapf who sent me yesterday a program to extract the 3 GROM of the TI-99/5 computer, it speeds things up. So, all is done: ROM and GROM are now dumped. This will permits to learn more about one of the rarest computers of the TI-99 serie and also opens the way to offer a MAME emulation of it. I sent all the files to Michael, I'm sure that he will do great things with them.
I have already begin to study the ROM/GROM: they already confirm that Texas Instruments has planned to propose a 64KB RAM 99/5 version (there is a embeded ROM/GROM/RAM test) . This great computer could have overshadowed a part of the 99/8 market.

I avail of this message to make an appeal again: Is there another person who owns a 99/5 too ? working or not. Always with the aim of learning more about this computer.

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Thanks, Fabrice. The GROMs are authentic - the CRC16 at 17FE/FF is correct for each of the three GROMs (0..2). GROM3 is the Editor/Assembler, and GROMs 4-7 are filled with FF. I guess there is also a CRC16 for the ROM, but we did not yet have a way to dump the "hidden" 8K yet, so the CRC16 of the ROM is supposedly at the end of that other 8K bank.

 

This will be the next step: Find out whether there is some indication of a ROM switch in the existing ROM. We can expect something like a write to ROM, or a CRU operation.

 

Edit: Fabrice, wouldn't it make sense to publish the dumps here so we have some more eyes looking at them?

Edited by mizapf
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wow, well done :)

maybe the ROM bank switching is like on the 99/2. There the CF40051 I/O Controller does the Chip select.

According to your motherboard there is a CF40067 that is close to the ROM Chip.

 

Here is the internal doc about the CF40051 for the 99/2:

http://ftp.whtech.com/datasheets%20and%20manuals/99-2%20Computer/TI992_IO_Controller_Chip.pdf

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I'm happy to please you with these dumps :)

Here is a link to an image disk containing all the ROM & GROM of the 99/5: http://www.ti99.com/99_5/DUMP_TI-99_5_ROM_GROM.DSK

 

EDIT:

Another solution to read the hidden 8 Kb CPU ROM: Extract the EPROM out of the motherboard and read it with my EPROM programmer :)

Edited by fabrice montupet
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Thank you so much for releasing this historical piece!

 

After this got a hot topic I decided to do some photos of internal docs that have been coming with the 99/8.

 

I think I have identified:

- TI-99/4B Speech Peripheral Spec (sadly only one page)

- Hex-Bus Memory Expansion Spec

- DRam Controller Spec (is this part of the Hex-Bus Memory Expansion Spec?

- Printer 850 (Omni) Specs? or is this something else?

- Winchester Disk System Spec

 

I thought I had more about the 99/4B but it's only one page. Maybe these are of help. I can do high-res scans as well.

internaldocs.zip

 

Further I have checked all disks images (transfered) that came from the 99/8 owner / TI Employee. But nothing related to 99/4B or 99/5 or 99/2.

The only thing I have found on them were 99/8 part lists, which I have published already in january.

 

Did you ever publish the 99/5 Memory Map?

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Klaus, thank you very much too for all these scans! They are full of interesting informations! it's Christmas before time, I am devouring them :-)
TI-99/5 and 4B documents are so rares that your Speech Peripheral Spec page is for me a great news.

Here is the 99/5 memory map (also published on my TI-99 website) :

0000 - 0FFF : ROM .5       8000 - 8FFF : CONTROL
1000 - 1FFF : ROM .5       9000 - 9FFF : CONTROL
2000 - 2FFF : EXP R1       A000 - AFFF : EXP R3
3000 - 3FFF : EXP R2       B000 - BFFF : EXP R4
4000 - 4FFF : ROM DSR      C000 - CFFF : EXP R5
5000 - 5FFF : ROM DSR      D000 - DFFF : EXP R6
6000 - 6FFF : ROM CART     E000 - EFFF : EXP R7
7000 - 7FFF : ROM CART     F000 - FFFF : EXP R8

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Interesting on the Hex-Bus memory device. With what we already had and this, you almost have enough data to try and reproduce it. . .the POLLO chip used as the DRAM controller is the same one used in the 99/8--and the full schematics for that are already up on WHT. What you are still missing is the interface portion to the Hex-Bus and the equations for the PAL14L4 used. You do have the signals to each pin, just not how they are being combined into the three outputs being used.

 

On the Winchester controller, the schematics go with the product specification manual I put up on WHT a long time ago. This fleshes out what is known of the device and gives the development timeline too. Considering that by the middle of the year, all of the 99/8 test machines were using the Myarc Personality cards and their SASI drives, I wonder if this just got turned over to Myarc as an outside project as their development would have overlapped the TI timeline. The timelines are just too close otherwise.

 

I'm not sure on the printer, at least not without a deeper review of the schematics. . .

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grom 3 is the E/A cart that was in there when you did the dump

grom 4-7 are not in use by the system it seems

grom 0-2 (99/4a uses 3 system groms as well): same token-set for TI Basic, same subprogram-set for TI Basic

 

But what is this in grom0?

GROM TEST 48K CPU RAM TEST64K CPU RAM TESTPHROM TST9

it's at address: >10F9

Is this in ROM for sure?

 

Grom0 offers next to the REVIEW MODULE LIBRARY the speed options as the 99/8:

SET SPEED

[1] NORMAL SPEED FOR GAMES

[2] FULL SPEED

 

Devices: CS1 and CS2 are listed in Grom0

 

Regarding Docs:

I have around 6 more hand written pages, mostly about 99/8, that I discovered within a Technical Manual. I will digitize them as well. Maybe it is of value for here as well.

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But what is this in grom0?

GROM TEST 48K CPU RAM TEST64K CPU RAM TESTPHROM TST9

it's at address: >10F9

Is this in ROM for sure?

 

Yes :)

And this is the first thing that I was pleased to see when I dumped the GROM

 

 

Grom0 offers next to the REVIEW MODULE LIBRARY the speed options as the 99/8:

SET SPEED

[1] NORMAL SPEED FOR GAMES

[2] FULL SPEED

 

The full speed setting works on my TI-99/5. I used it when I showed you a video playing Parsec a few months ago.

I don't know for your 99/8 Computer but on mine this low/full speed settings dont work: when I choose the low speed option, the 99/8 is always at full speed.

 

 

Devices: CS1 and CS2 are listed in Grom0

 

The 99/5 has a tape port. I still haven't used the CS1/CS2 option to load/save programs (I only use my Hexbus floppy drive). I will do that. But I think that it works.

 

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The 99/5 has a tape port. I still haven't used the CS1/CS2 option to load/save programs (I only use my Hexbus floppy drive). I will do that. But I think that it works.

 

 

Yes, it should work. The 99/8 and 99/2 have instead of the DB9 the 3 dedicated ports for Tape Recorder connection. Do you have that other cable in original?

 

Shouldn't the dump contain the Device HEXBUS somewhere as well?

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If you compare it with 99/8 Roms, this contains the Devices in the rom1.u25 file:

RS232

RS232/1

RS232/2

DSK

DSK1

DSK2

DSK3

DSK4

HEXBUS

 

I couldn't find the search code for ROM only module, did you try out a ROM only module in the 99/5 cartridge port?

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Here are the promised 99/8 and Hex-Bus notes I have discovered within the 99/4a Console and PEB Technical Manual of the 99/8 seller:

post-27826-0-37440800-1479153746_thumb.jpg

post-27826-0-84031100-1479153765_thumb.jpg

post-27826-0-76209900-1479153785_thumb.jpg

post-27826-0-77189800-1479153805_thumb.jpg

post-27826-0-35806300-1479153826_thumb.jpg

post-27826-0-92321400-1479153836_thumb.jpg

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All the Hexbus commands are implemented on the 99/5, I can read/write floppy disks, format or catalog them and all other things else.

That's done. I have tested the cassette port with a TI tape recorder (the beige one for fun) and, as I imagined, it works. It just for information because I think that I will never use again, with the use of floppy disks, the tapes have no more interest.

The 4B documents on whtech surprised me when I discovered them a few years ago. Because, in one of them, the system bus pinout seems to present the I/O bus on a 60 pin connector. And it differs than what I saw on a rare picture of the TI-99/4B motherboard. This picture having a very poor quality, I made a simplified schematic of the motherboard by studying the picture previously enhanced with an image correction program. Here is what it gives:

ti994b0.jpg

Lets compare with the TI-99/5:
ti995_0.jpg

As you can see, the TI-99/4B and the TI-99/5 have major differences. They are two different computers.

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I couldn't find the search code for ROM only module, did you try out a ROM only module in the 99/5 cartridge port?

I have tested cartridges like the Atari ones that only contain ROM, they are not recognized. Not surprised, Texas Instruments hated these sort of third-party cartridges.

 

EDIT: Thank you so much for these Hexbus documents!

Edited by fabrice montupet

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I have tested cartridges like the Atari ones that only contain ROM, they are not recognized. Not surprised, Texas Instruments hated these sort of third-party cartridges.

 

Just think, they found the SolutionTM to their problems with the QI console. No wonder that they continued with it, anything else would have meant a concession of that folly and the poor engineer would have to give back his raise.

 

(Message may contain traces of irony.)

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