Tandy graphics

[Vorticon]

Hi.
I keep reading that Tandy graphics are essentially the same as those of the PCjr, yet whenever I choose Tandy graphics in a game (such as FS3 for example), the screen image is marred by horizontal black lines. Is there a patch available to fix that problem?

Walid

[Brutman]

Have you done the Tandy modification to the hardware first? Tandy borrowed from the PCjr on the video card, but enhanced it too. There is a relatively minor modification to make the PCjr more 'Tandy' compatible.

(I've not bothered doing it, but I know there are docs floating around.)


Mike

[Vorticon]

Would it affect the standard PCjr graphics operations?

Walid

[MattCarp]

There's a switch to enable or disable the modification.

I did it on one of my machines. I can't say I ever noticed the difference. It only makes sense for a few games that we coded to take advantage of the Tandy enhanced graphics capabilities. Personally, I don't think it's worth it and remain saddened by the hole and dorky switch installed in the back panel of my original machine....

[Vorticon]

Would you happen to remember the procedure for the modification? I actually have a couple of games like FS3 and Silent Service II that have a Tandy graphics option that I would like to try. Since it is a switchable option, I don't see the harm in having it available.
I have looked all over the internet for the instructions of that hack and could not find an actual document. All I know is that it involves an LS 7400 family chip piggybacked to another chip and a few jumper wires...

Walid