Shaky screens

Rumble · Post by **Rumble** » Sat 05 Feb, 2005 1:24 am

I have a TI 84+ SE and run MirageOS on it, and my games usually run fine on it. But when I play certain Ion games like Super Mario v1.2, Acelgoyobis, Desolate, and Phantom Star, the screen tilts ans shakes up and down quickly. Can someone tell me how to fix it?

Thanks

Post by **tr1p1ea** » Sat 05 Feb, 2005 1:41 am

Big problem with some of the new 84+'s ... some have crappy display controllers ... i think the display routines for all thos game need to be modified but since many of us dont have 84+'s to text with it may take some time.

Guest · Post by **Guest** » Sat 05 Feb, 2005 1:47 am

Oh well. They're still playable. It's just very annoying.

Jim e · Post by **Jim e** » Sat 05 Feb, 2005 2:00 am

I don't see why it shouldn't be as easy as increasing the LCD driver speed port. I don't think rewriting every game would be necceary.
The crappy drivers on the 83+ though would probably be harder to fix.

Mike K · Post by **Mike K** » Sat 05 Feb, 2005 2:20 am

Dan has been working on a fixed version of MirageOS that fixs this issue. I beleive it is still in beta, however.

-Mike

Post by **tr1p1ea** » Sat 05 Feb, 2005 2:27 am

Jim e, i said that the display routines will need to be re-written. Exactly what you said, they probably need a larger delay between writes ... not sure how this will effect the grayscale though ... thats why it needs testing.

Guest · Post by **Guest** » Sat 05 Feb, 2005 2:34 am

Mike K wrote:Dan has been working on a fixed version of MirageOS that fixs this issue. I beleive it is still in beta, however.

-Mike

Could I test the beta?

Post by **tr1p1ea** » Sat 05 Feb, 2005 3:01 am

An updated MirageOS wont help games like Desolate, Phantom Star and perhaps Acelgoyobis as they have their own fastcopy routines.

Well you never know ... it is bound to be littered with hooks of all kinds

.

CalcKing · Post by **CalcKing** » Sat 05 Feb, 2005 3:40 am

I may be completely mistaken but I think I remember Phantom Star being fixed by the beta version of MirageOS that I have...

Sorry to those who would like a beta copy of v1.3, but it is not supposed to be distributed by those who are "testers."

Jim e · Post by **Jim e** » Sat 05 Feb, 2005 4:22 am

Tr1p, I meant the extra hardware on the 83+se & 84+(se). Port $29 and $2A add delays when ever you read from or write to the lcd driver. ON a normal 83+ it only takes 11 tstates to "out ($11),a", but on an SE it takes about 15 tstates.
I know this because I've been resreaching hardware that might help my grey routine. Interrupts, Crytals timers, LCD driver, LCD speed, & CPU speed. So far Michael V's Port Refernce has been an invaluable source, but it's incomplete. And before I can go much further, I'm probably going to have to buy an 84 this week.

I think I got off topic...

Post by **tr1p1ea** » Sat 05 Feb, 2005 4:33 am

Yeah ive messed a little with beridding delays and such on the SE ... but not much.

I am in need of a '+' calculator and i might be getting an 84+ myself really soon

.

Post by **DarkAuron** » Sat 05 Feb, 2005 4:35 am

While you can change the LCD speed, for some reason the faster you make the LCD speed, the slower the opcodes in the routine run. So it ends up taking even longer.. MV is looking into this, but it's a bit unknown as far as I'm concerned.

Jim e · Post by **Jim e** » Sat 05 Feb, 2005 5:02 am

I've gathered some information on it, It seems that The lcd speed port ($29) only uses bits 2-7 to determine the added lcd delay, and bits 0-1 are tied to the CPU speed port($2E), don't ask how i'm still experimenting but they should both be set to zero so not delay all opcodes...I think.

One more thing, Desolate is messing up?!? Last I saw the timings on GPP were about 77 tstates. *runs and checks code*, I see the shortest delay is 65 clocks right before starting a new column, I 'm surprised the 84+'s driver sucks that bad.

Guest · Post by **Guest** » Sat 05 Feb, 2005 5:08 am

Jim e wrote:One more thing, Desolate is messing up?!? Last I saw the timings on GPP were about 77 tstates. *runs and checks code*, I see the shortest delay is 65 clocks right before starting a new column, I 'm surprised the 84+'s driver sucks that bad.

Well, Desolate is a little different than the others. First it shakes and tilts, then it just freezes the entite calculator and deletes random stuff. Weird.

CoBB · Post by **CoBB** » Sat 05 Feb, 2005 7:44 am

Worst of all, no emulator replicates this behaviour. In VTI you can write to the LCD at maximum speed and it will look right. I did it when I was coding Traz: I didn't know of fastcopy routines at the time (even better, some moron told me on TI-Files that the romcall is the fastest I can get), and I wanted to make it faster by only updating the at most 12 bytes covered by the ball by a special sprite routine that worked directly on the LCD screen. It was perfect on VTI, but on the real calc it just resembled what it should have been -- it garbled the screen on the way of the ball.