Omnimaga

Omnimaga => News => Topic started by: critor on June 21, 2012, 10:17:33 am

Title: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: critor on June 21, 2012, 10:17:33 am
The TI-89 has a 160x100 LCD.
The TI-92 and TI-Voyage 200 have a 240x128 LCD.

But you can run TI-92 Plus assembly games on the TI-89 and their display won't be corrupt.
The only problem is that the display is cropped:
(http://i43.servimg.com/u/f43/13/23/13/53/450410.gif)
(http://tiplanet.org/forum/gallery/image.php?mode=medium&album_id=13&image_id=1108)

It means the all those calculators are sharing a 240x128 display buffer, which is partially displayed on the TI-89.



All those calculators accept a 240x128 TI-ViewScreen panel, usually used by teachers to show the display to the whole class.

In the case of a TI-89, only the top-left part of the panel is used with the OS:
(http://tiplanet.org/forum/gallery/image.php?mode=medium&album_id=9&image_id=1094)



In that case, what would happen if an assembly program wrote data in the screen buffer outside the 160x100 zone?
(http://tiplanet.org/forum/gallery/image.php?album_id=13&image_id=1109&view=no_count)
Success! Although the game display is cropped on the TI-89, the whole screen buffer is displayed on the external panel. ;D(http://www.omnimaga.org/Themes/default/images/gpbp_arrow_up.gif)



But of course, this was a VSC version of the TI-89 with the additionnal proprietary  ViewScreen connector.
The panel can be plugged on every TI-89 Titanium using an adaptator for the mini-USB connector: the TI-89 Titanium Presentation Link.
(http://tiplanet.org/forum/gallery/image.php?mode=medium&album_id=9&image_id=1095)

So using this adapter, can this extended display been achieved on all TI-89 Titanium calculators?
(http://tiplanet.org/forum/gallery/image.php?mode=medium&album_id=13&image_id=1110)
Success, again! ;D(http://www.omnimaga.org/Themes/default/images/gpbp_arrow_up.gif)



So it's quite interesting! :D
If someone has the time, it means we could develop an external 240x128 display for the TI-89 which would be plugged through the mini-USB port, the 1st step into performing some kind of an "upgrade" of the TI-89 into a TI-92 Plus / TI-Voyage 200. ;D(http://www.omnimaga.org/Themes/default/images/gpbp_arrow_up.gif)



Credits for the idea of the experience go to Lionel Debroux.



Source with more information and images:
http://tiplanet.org/forum/viewtopic.php?t=9511&p=125807
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: apcalc on June 21, 2012, 10:34:42 am
Wow!  This is fascinating news!  Great work critor! :)
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: Juju on June 21, 2012, 10:38:15 am
That is pretty nice :D
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: blue_bear_94 on June 21, 2012, 10:45:24 am
Why hasn't anyone noticed this before?
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: Adriweb on June 21, 2012, 12:10:11 pm
Well these viewscreen are rare for students :P
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: aeTIos on June 21, 2012, 12:14:14 pm
Would this also be possible for the 84+?
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: TravisE on June 21, 2012, 12:23:22 pm
That's pretty cool. If you were writing just TI-89(t) programs, you could probably use the extra space for debugging info or something, or hidden messages. :P That sort of reminds me of once when I was fooling around in Command Post Plus and poking in random bytes like my name in the off-screen area of the 89 LCD buffer. If you don't reset the calc or run ASM programs that use the full buffer, it can invisibly remain there for quite some time. :)

It would be cool if someone found a way to make an inexpensive external display. Or even a large, bright LED display, hehe.
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: blue_bear_94 on June 21, 2012, 12:27:04 pm
Quote from: aeTIos on June 21, 2012, 12:14:14 pm
Would this also be possible for the 84+?
No, because the 84+'s buffer is only 94x64.
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: calc84maniac on June 21, 2012, 02:17:51 pm
Quote from: blue_bear_94 on June 21, 2012, 12:27:04 pm
Quote from: aeTIos on June 21, 2012, 12:14:14 pm
Would this also be possible for the 84+?
No, because the 84+'s buffer is only 94x64.
Actually, it's 120x64. I'm sure that a program that reads LCD commands from the USB would be able to display that whole area.
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: parserp on June 21, 2012, 03:57:32 pm
Quote from: calc84maniac on June 21, 2012, 02:17:51 pm
Quote from: blue_bear_94 on June 21, 2012, 12:27:04 pm
Quote from: aeTIos on June 21, 2012, 12:14:14 pm
Would this also be possible for the 84+?
No, because the 84+'s buffer is only 94x64.
Actually, it's 120x64. I'm sure that a program that reads LCD commands from the USB would be able to display that whole area.
Where are you getting all these extra pixels? O.O
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: aeTIos on June 21, 2012, 04:07:10 pm
^that :o Really cool stuff O.o
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: tr1p1ea on June 22, 2012, 12:36:33 am
It looks older LCD drivers on older calcs like TI-82/TI-83(+) ran with T6A04/T6A04A @ 120x64 and the newer calcs like the TI-83+SE/TI-84+(SE) ran with the T6K04 which is 128x64.

Would be interesting to see if this applied.
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: aeTIos on June 22, 2012, 02:16:46 am
Well, indeed :D I would be positively surprised if this happens.
How long would it take for the USB port to send 1024 bytes of data?
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: willrandship on June 22, 2012, 11:32:09 pm
this is all extremely interesting. I'm not surprised at all that they did it on the 89, but I would have thought that 96x64 controllers would exist. Makes me wonder why they didn't just use the full resolution. The 86 did extremely well with it, after all.

So, theoretically, couldn't you just hook up a new internal LCD? (I say 'just' but it's really not that easy :P) or are there not enough pins on the connectors?
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: calcdude84se on June 24, 2012, 01:53:25 pm
Quote from: calc84maniac on June 21, 2012, 02:17:51 pm
Quote from: blue_bear_94 on June 21, 2012, 12:27:04 pm
Quote from: aeTIos on June 21, 2012, 12:14:14 pm
Would this also be possible for the 84+?
No, because the 84+'s buffer is only 94x64.
Actually, it's 120x64. I'm sure that a program that reads LCD commands from the USB would be able to display that whole area.
Actually, it depends on the calculator. Mine, as I've determined from several tests, is 96x64. The most important result is that, when the LCD is in Y-autoincrement mode, after the 12th/16th column (8-/6-bit mode, respectively) it wraps back to the first column, not an invisible one offscreen. Mine's also the one with the extra commands to flip the display, which gives me the impression it's a different driver.
Title: Re: Extend your TI-89 display to 240x128 (TI-92 size)
Post by: critor on July 18, 2012, 08:06:45 am
A first way to add an external 240x128 screen to your TI-89 Titanium is to build an USB adapter like the one from TI:
(http://tiplanet.org/forum/gallery/image.php?mode=medium&album_id=9&image_id=1103)

See here for additional info:
http://tiplanet.org/forum/gallery/image_page.php?image_id=1103

Note that it's mainly build around a FlashROM whose content is unknown to us - which might not be easy.



Another way is to start from the internal J3 connector:
(http://www.datamath.org/Graphing/Images/TI-89_Titanium_FR06_PCB.jpg)(http://tiplanet.org/forum/gallery/image.php?mode=medium&album_id=9&image_id=1165)

See here for additional info:
http://tiplanet.org/forum/viewtopic.php?f=42&t=9658