Thanks to calc84maniac:
{E8447}->A will store the current TIOS contrast in A (E is the ^10 symbol, the little E)
A:Asm(7DC6D8D310) sets the contrast to A

Aaah nice.

I was quite lucky to see this in Cemetech TI-SAX on my visit on Kerm site  and kinda feared I would forget

Basically we can store memory stuff to variables such as the contrast. I wouldn't be surprised if there were more we could do. I will have to check WikiTI for some more stuff. I, for one, am curious where is stored the screen shift position in the memory, because messing with this can become handy for earthquake effects (altough WabbitEmu won't render them )

@Calc84: noted. When I worked on ROL2 I messed around after backing up with ZCON (Michael_V) and tried to set lower or higher values to this and it effectively can do weird stuff. Same for screen shifting past 128 or 256 (I forgot)

Nice

Hey, I just took a look over my HL2 box...did you know the top of your lambda is backwards in the logo?

Ouch, that sucks

This is a bit why I dislike hex for storing pic, sometimes. I always loved how iN BASIC and libs you could edit pics directly, then immediately run the game to test, since the sprites were inside the pic.

Actually, if you run Axe, then sometimes the current screen is left of the graph screen, so you could store it to a pic from there.

Yeah, I'm sure I can work it out.  Thanks!