TI(ny)-99/4A Computer

[+Schmitzi]

unbelievable

[mglafond]

1 hour ago, fabrice montupet said:

Finally, I have chosen the V9958 as the standard VDP of the computer. Hope that I have made the good choice.  And I have just finished its integration and the 128 Kb of VRAM on the motherboard. Of course, it will be possible to upgrade the VRAM to 192 Kb by piggybacking two DRAMs, I have placed a pin header for CASx). I had to greatly modify the routing of the motherboard, it was an opportunity to rethink the SAMS 1MB Memory Extension part (expandable to 4MB). Now a daughter card is no longer necessary, all the RAM memories of the SAMS extension are integrated into the motherboard (so an even more tiny motherboard ? ).

Note that the working V2.5 motherboard has a TMS-9918A/29A VDP

Here is a drawing showing the final organization of the TIny-99/4A v2.9. The presence of a cartridge gives a better idea of computer size:

Click on the picture to enlarge it.

 

These last modifications complete the development of the microcomputer...finally!

 

 

Looks like beautiful work, Fabrice!

[+mizapf]

I always wondered why the mouse is so rarely used (among all systems with 9938). The mouse has a simple interface and works reliably, with two buttons (via 9938).

 

Edit: Just to explain, the 9958 has no option for connecting a mouse. In turn, it has some more features and a larger color palette. I noticed that the EVPC2 already allowed for using the 9958 instead of the 9938, also explaining that the mouse interface was rarely used. If I had written more programs for the Geneve, I would have tried to employ the mouse as often as possible, but so it's just one major program (Fractals), which actually needs the mouse. So is it really the better graphics, the problems to still find a suitable mouse, or the availability of the chip?

 

Regardless of the 9938/9958 decision, this is certainly a fantastic work of Fabrice.

Edited January 20, 2021 by mizapf

[+Ksarul]

2 hours ago, fabrice montupet said:

Finally, I have chosen the V9958 as the standard VDP of the computer. Hope that I have made the good choice.  And I have just finished its integration and the 128 Kb of VRAM on the motherboard. Of course, it will be possible to upgrade the VRAM to 192 Kb by piggybacking two DRAMs, I have placed a pin header for CASx). I had to greatly modify the routing of the motherboard, it was an opportunity to rethink the SAMS 1MB Memory Extension part (expandable to 4MB). Now a daughter card is no longer necessary, all the RAM memories of the SAMS extension are integrated into the motherboard (so an even more tiny motherboard ? ).

Note that the working V2.5 motherboard has a TMS-9918A/29A VDP

Here is a drawing showing the final organization of the TIny-99/4A v2.9. The presence of a cartridge gives a better idea of computer size:

Click on the picture to enlarge it.

 

These last modifications complete the development of the microcomputer...finally!

 

 

C'est magnifique! Merci beaucoup, Fabrice!

[RXB]

OK BIG QUESTION HOW MUCH?

 

[mjnurney]

This looks fantastic!

[RickyDean]

WOW!!!!

[GDMike]

I suppose a regular rs232 card, ramdisk can still plug into the exp port.

This is beautiful

[fabrice montupet]

Thank you all so much!

Now the development is end, I will able to find the suppliers for all the components, only good quality ones will be retained. I'll do my best to find the better price and I will back to you to tell you.
I have hesitated a long time between the V9938 and the V9958 because of the mouse support on the first one. But the horizontal & vertical hardware scrolling and the better again palette gained the upper hand. And I concluded that a mouse could be added using a serial card installed the an expansion slot. Yes, all the 3 slots are fully PEBOX compatible. Besides you can see on all the videos that a TI PHP1220 and a TI PHP1240 are installed on the Tiny-99/4A v2.

[gferluga]

Can't wait to turn it on... ??⌨

[fabrice montupet]

Thank you! ?

A first batch of 5 PCB has been ordered, I think that I'll receive them in about a week.

I made a last update of the PCB before sending it for production:

 

You can see the V9958 footprint, this VDP became the default VDP that will be delivered with all TIny-99/4A v3.  But you can also see a cabled DIP 40/600mil footprint. It will permit to install a TMS-9918A/29A VDP based daughter board for those who will prefer the original VDP or the F18A or F18A MK2 for those who like to use the modern VDP ?

 

Edited March 8, 2021 by fabrice montupet

[RickyDean]

4 hours ago, fabrice montupet said:

Thank you! ?

A first batch of 5 PCB has been ordered, I think that I'll receive them in about a week.

I made a last update of the PCB before sending it for production:

 

You can see the V9958 footprint, this VDP became the default VDP that will be delivered with all TIny-99/4A v3.  But you can also see a cabled DIP 40/600mil footprint. It will permit to install a TMS-9918A/29A VDP based daughter board for those who will prefer the original VDP or the F18A or F18A MK2 for those who like to use the modern VDP ?

 

Wow!!!

[GDMike]

Can the OS be changed to a forth kernel or something else besides the option for basic.

Edited March 9, 2021 by GDMike

[fabrice montupet]

The GROM 0, 1 and 2 are stored in an EPROM, so you can do all that you want ?

 

[fabrice montupet]

After some problems (difficulties to gather all components, delays and a lost on components package ) I was finally able to assemble the V3 motherboard, and it works fine
I just had a little worry on the first startup: the display was distorted and after some investigation, I found the guilty: the shrink-dip 64pin socket that I used for the V9958. As the package containing (in other things) the turned contact socket for the VDP has been lost, I had to use what  I had in a spare box: a dual leaf socket. I don't like these sockets because of their poor contacts and obviously they do the same for me... I  straightened the faulty leaf and all worked !  It is funny that we talked not long ago about the choice of the sockets types in an other thread.

The V3 computer is running like a charm near continuously since two days.
On this motherboard version, there are mainly two upgrades: SAMs RAM are not on a daughterboard anymore, all is embedded on the motherboard.  The VDP 9958 and its VRAM as remplaced the TMS9918A/29A.

 

 

 

 

[+Schmitzi]

Really amazing thing ! Love it.

What if we had this, back in the days ?  ?

 

 

 

[fabrice montupet]

Thank you!
It was a childhood dream, it's done ?

 

[Shift838]

1 hour ago, fabrice montupet said:

After some problems (difficulties to gather all components, delays and a lost on components package ) I was finally able to assemble the V3 motherboard, and it works fine
I just had a little worry on the first startup: the display was distorted and after some investigation, I found the guilty: the shrink-dip 64pin socket that I used for the V9958. As the package containing (in other things) the turned contact socket for the VDP has been lost, I had to use what  I had in a spare box: a dual leaf socket. I don't like these sockets because of their poor contacts and obviously they do the same for me... I  straightened the faulty leaf and all worked !  It is funny that we talked not long ago about the choice of the sockets types in an other thread.

The V3 computer is running like a charm near continuously since two days.
On this motherboard version, there are mainly two upgrades: SAMs RAM are not on a daughterboard anymore, all is embedded on the motherboard.  The VDP 9958 and its VRAM as remplaced the TMS9918A/29A.

 

 

 

 

 

Now that's a beautiful board!

 

I am sure many of us will be very interested to get one of these in our collection when you work out the pricing.  I know I am!

 

 

[+9640News]

I'm looking at the most recent photo, and the placement of the capacitor and other chips around it.  Will this motherboard require new designed cards to plug into it, or will existing cards plug into the connectors?  I'm thinking a number of cards would not seat completely.

[oddemann]

3 hours ago, fabrice montupet said:

Thank you!
It was a childhood dream, it's done ?

 

Could you make a video of V3 in action with carts and different stuff?

Looks Great, and great does not do it justice! Congratulation on an ATX TI motherboard.

So if I have a not working TI, with lots of parts, how would that work out? (If I was to ask for a V3)

[fabrice montupet]

@9640News:

An optical illusion could give the impression that the radial capacitor placed near the expansion Slot 1  (situated at the border of the motherboard)  prevents the insertion of a card. This slot has been used to receive several TI cards like the PHP1240 Floppy Disk Controller, the PHP1220 RS232 and the PHP1270 P-Code one. I also tested the Horizon RAMDisk card and the CorComp 9900DS/DD and all of them fit well without touching the capacitor. In fact, I have respected the TI specs.
But, you're right, some productions that do not reproduce the original TI cards shape could cause problem to fit. I think about the cards like the SNUG ASCSI. That said, the problem can be easily circumvented:
- The Slot 3 accepts directly this such card.
- The Slot 2 and Slot 1 can accept it too if the Speech PHROM are soldered on the motherboard and not socketed.
Note that this capacitor near the Slot 1 is totally  unecessary if the power supply used feeds correctly.  I have installed it just for some motherboard powering tests with exotic power supplies.

 

Videos arrive soon,  maybe tomorrow ?

[fabrice montupet]

To give you all my thought during the project I tell you my lasted idea before its finalization. As I was ending the last routing modification before the creation of the Gerber files, I had the idea to kill two expansion slots and to install a 3 slots 90° adapter riser card in the remaining slot. Thus all the 3 expansion cards would be on the horizontal plane, above the motherboard. Removing the two slots would have allowed me to integrate a serial or a parallel interface on the motherboard, with still a lot of routing work because everything is really condensed. I hesitated for a long time if I put into practice this idea.

Any project can be improved again and again, it is for this reason why the TIny-99 / 4A has never ceased to evolve since the beginning. But perhaps one have to say to ourselves at some point that we must put an end to upgrades to avoid endless development.

Edited April 15, 2021 by fabrice montupet

[+Schmitzi]

Samba Ole ? Riser card and RS232 sounds p*e*r*f*e*c*t , plus ALL PEB-cards will fit

[RickyDean]

2 hours ago, fabrice montupet said:

To give you all my thought during the project I tell you my lasted idea before its finalization. As I was ending the last routing modification before the creation of the Gerber files, I had the idea to kill two expansion slots and to install a 3 slots 90° adapter riser card in the remaining slot. Thus all the 3 expansion cards would be on the horizontal plane, above the motherboard. Removing the two slots would have allowed me to integrate a serial or a parallel interface on the motherboard, with still a lot of routing work because everything is really condensed. I hesitated for a long time if I put into practice this idea.

Any project can be improved again and again, it is for this reason why the TIny-99 / 4A has never ceased to evolve since the beginning. But perhaps one have to say to ourselves at some point that we must put an end to upgrades to avoid endless development.

That is your decision, and you have produced an exceptional piece of work here, so I would be happy either way.

[Asmusr]

Very impressive.