Insight into the TI-99/4A QI Model

[horizon2374]

Do Funware carts work with QI models with the original ROM (non-v2.2)? I recently bought a Funware cart it’s not working only shows 1 FOR TI BASIC. All other 3rd party carts (Atarisoft & Parker Brothers) working fine.

[+Ksarul]

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.

[Gary from OPA]

BTW, it is easy enough to add back the CRU control lines to the cartridge port (just a couple of wires to run), i can't recall if anyone wrote up a tutorial on how to do it in the past, but would be handy to recreate or make one, to get certain cartridges like my own POP-Cart working and others that use the CRU for rom/bank/control switching, etc.

[+Ksarul]

14 hours ago, Gary from OPA said:

BTW, it is easy enough to add back the CRU control lines to the cartridge port (just a couple of wires to run), i can't recall if anyone wrote up a tutorial on how to do it in the past, but would be handy to recreate or make one, to get certain cartridges like my own POP-Cart working and others that use the CRU for rom/bank/control switching, etc.

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.

[+acadiel]

On 12/16/2023 at 2:45 AM, Ksarul said:

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.

Yep.  If they don't need the SuperSpace II cart, and it's using a non 2.2OS then the ROM cart conversions of the CRU carts will work for those former DBT CRU carts.  (I have an archive of them I put somewhere on here - it's getting hard to keep track.)  CRU usage on 2.2 would only be for purists who want to use the original CRU based carts on a 2.2 *or* a SuperSpace II cart.  Otherwise, it wouldn't be needed unless it was V2.2.

 

I think we could easily get a replacement GROM0 to just drop into a V2.2 nowadays - there's enough spare parts consoles laying around.  Or a bootable pass thru DSR board for the right side (aka a GROM buster alike board) to probably patch the v2.2 boards pretty easily nowadays.  We know what the differences are, don't we?  (Or, like CBM does, a daughter board for GROM0 that can fit in there that simulates a regular GROM0.)

 

[atrax27407]

Do we have the circuitry for a daughter board to replace GROM0? If so, an EPROM replacement is entirely feasible. I have several "flavors" of GROM0 in my collection.

[+acadiel]

4 minutes ago, atrax27407 said:

Do we have the circuitry for a daughter board to replace GROM0? If so, an EPROM replacement is entirely feasible. I have several "flavors" of GROM0 in my collection.

Yep - 

 

 

[atrax27407]

Let me know what you need for a GROM0 file.