I'm going to be streaming a live unboxing of the TI Presenter hardware at 9PM Eastern tonight:

http://www.ustream.tv/channel/brandonlw-live

It's significant because this is usually a very hard to find (for cheap anyway) and expensive piece of hardware that connects to TI graphing calculators -- upwards of $350.

This stream will have the unboxing of the TI Presenter as it was shipped to me, first impressions, connecting a standard TI-84 Plus and TI-84 Plus Silver Edition to a TV through the use of a Presentation Link adapter, and if you stick around, maybe some exciting discoveries about how the hardware works and how the OS talks to it, and maybe even learn a little more about how direct USB on the 84+/SE actually works.

The TI Presenter is also Flash-upgradeable and can theoretically be upgraded from a connected graphing calculator.

I hope it's as exciting for you guys as it will be for me.

I'd be watching this if I wasn't watching the season finale of Chuck......does anyone plan to record and youtube it for the rest of us?

Ustream will actually save it. The real question is, why can't you record Chuck and watch it later?

it will be available for torrent later, elfprince, you must watch brandon open his presenter with the rest of us, no excuses. :p

Ah, woot. Chuck already is recorded, and happens to be the follow-up to making dinner with my girlfriend

Awesome, BrandonW; glad you finally got all the issues with UPS and its epic retardation worked out. I look forward to the unboxing, and hope you can figure out what magic makes it work the way it does (hint: I hope it's software, not hardware).

As you guys may or may not know, the stream was full of fail last time because my TI Presenter didn't come with a Type I cable to make the actual connection between the calculator and TI Presenter. I ordered one, and it just arrived today.

So the unboxing will resume tonight at 7PM EST. On the agenda:

Connect the 84+/SE to the TI Presenter for the first time
Observe how it works (i.e. hardware assistance or all in software)
Try connecting Merthsoft's ViewScreen 84+SE with broken LCD to it to see what happens
See if it's possible to turn on/off screen output from the calculator or output our own contents
Find a way to sniff traffic between calculator and TI Presenter to see what requests are happening (not sure how if it's hardware-assisted)
Resume work on upgrading the TI Presenter firmware over I/O from a calculator
Play calculator games on my TV!

Hopefully it'll be fun, and I hope you guys can be a part of it!

Sounds like lots of fun! I know I'll be watching. Will we be able to chat with you via #cemetech, like the last several streams?

I'll sure be part of it!

I know this would all be speculation at this point, but are you still convinced that it must be done in hardware somehow? I believe you mentioned at some point that you can't find any code in the OS that would be responsible for this, unless I misunderstood.

Yes, you could do that or you could use #ti, which seemed to be the main channel last time for this stream.

If other talk is going on in #ti, we shouldn't flood it with seemingly nonsensical one-sided talking, but I don't think that'll happen.

#cemetech could work, if during evenings there aren't like 3 conversations going on at once like in #omnimaga or #tcpa. Otherwise, I guess #ti could do

As you probably saw, the unboxing went well and I successfully connected a non-ViewScreen TI-84 Plus Silver Edition (with the aid of the USB Presentation Link adapter) to my TV via the TI Presenter.

From the to-do list:



Done, and works.



It's done with extra hardware that (more or less) redirects port outputs from 10h and 11h to port 0A2h, which is the outgoing pipe for the Presentation Link adapter. This extra functionality from the controller is toggled with a 0 or 1 to port 5Ah.



Nothing, he totally killed that poor thing's LCD. Still works fine, however.



It can be turned off with port 5Ah as above. It took all night, but I finally managed to output our own contents. It turns out that the calculator just sends two-byte packets that correspond to port 10h/11h outputs: the first byte is the value written to the port, and the second is the port offset (00h for port 10h, 01h for port 11h).
So for example, to turn on the LCD, send: 03 00
Or to write 8 black pixels at the current LCD coordinates (assuming 8-bit mode): FF 01

I've created a proof-of-concept application at http://brandonw.net/calcstuff/vs8x.zip and http://brandonw.net/svn/calcstuff/VS8x/trunk/ that will either output a grid of vertical lines or the contents of a specified Pic variable, independent of the LCD's current contents.



This was done by writing a peripheral driver (meaning hacking up periph8x) to have an 84+ pretend to be a Presentation Link adapter. The host calculator read the peripheral's vendor/product IDs, assumed it was a Presentation Link adapter, enabled its port mirroring hardware, and started sending data. And then lots of staring at the data was done to find the above pattern.



I'll get to this sometime. I have an idea about creating a poor man's hardware I/O protocol analyzer by linking two 84+/SEs via direct USB, and running a program on both that would redirect I/O TI link protocol packets back and forth between calculator 1 and calculator 2. You could place this setup between the TI Presenter and PC, or calculator and PC, or whatever, to log and study what's being transmitted between the two. It would require some fairly icky direct USB stuff, but I think it has potential. If I ever find the time...



The port mirroring hardware works outside of interrupts and basically everything else, which is good, but either the Presentation Link adapter or the TI Presenter requires more LCD delays than the built-in LCD controller. The built-in LCD delay routine at 000Bh deals with the Presentation Link (it sets 3,(iy+41h) when the device is attached and adds more delays if so), but because most games use their own LCD delay routine for speed, it doesn't work quite so well. It also rules out the possibility of grayscale on the TV because the thing is just depressingly slow.

So it wasn't a total waste...thanks everyone for sharing in my giddy outbursts. It's a lot more fun when other people are involved, even if just lurking.

Thanks for the update, BrandonW! It's always fun to watch you debugging and getting super-excited when you figure something out. How that you've gotten this far with decoding what's going on, what do you have planned for the device? Do you have any plans to further develop imitating either end (the Presenter or the calculator/OS sending Presenter data)?

Not really, considering that these things are so expensive and I'm probably the only one that's ever going to own it. Not much point in developing something if I'm the _only_ one that can use it.

I'd like to turn this application into a tiny little Calcsys-for-TI-Presenter, allowing Flash upgrades and so on. It might be fun to write a little something for the other end, a calculator pretending to be the Presentation Link and showing on its LCD what the other calculator's LCD has.

It really depends on how the TI Presenter firmware disassembling goes, and I owe you (all) high-res pictures of it to maybe get somewhere with it. I think we can modify it easily (no validation), so if we can actually understand TI's firmware, maybe we can write our own or modify theirs to accept uploads of temporary games or something wacky like that.

EDIT: I uploaded a YouTube video with all the TI Presenter findings at http://www.youtube.com/watch?v=llouoOYRMAE .

/me thinks we should have another Brandon Wilson shows the community all the cool stuff in his apartment night.

Here, I fixed it for you:
/me thinks we should have another "Brandon Wilson shows the community all the cool stuff in his apartment" night.

That removes the ambiguity that perhaps you want other community members to show off all the cool stuff in their apartment.

It wasn't that ambiguous to begin with. postcount++

Agreed.

++

I just watched your video on Youtube, and it seemed to me that a cooler potential application, would be reverse analyzing the protocol and constructing our own TI-Presenter compatible device, for whatever purposes you may choose. Is the increased LCD delay time inherent in the calculator's behavior in mirroring LCD contents to USB, or in the presenter's ability to display contents being sent?