This is interesting. Does it retain its memory after you unplug it? How big is it?

I've read about these on the mailing list archives a long time ago. I believe they either use Flash ROM, or some type of power source so that they keep their power when unplugged.

Oops, I meant that I believe they keep their /memory contents/.

From now on I'm going to wait five seconds longer before hitting the 'Post' button.

Bleh, EPROMs and PIC programmers are so expensive where I am. So much so that it would be cheaper to get the 89Ti *almost*
Are there any programs out there that can recieve programs from a USB Thumbdrive? (83+ in particular / USTORAGE device)???

This should be doable. Most thumb drives use USB Mass Storage drivers on the PC so the command structure is well known. The problem will be creating the illusion that the thumb drive is connected to a host. This would require a USB host chip. They are now available with the new USB OTG (On The Go) specification emarging, but they are not standalone chips. Another microcontroller would have to be used to control that chip, so it looks like this is the best there is now. Other options do exist. MMC cards have a good potential for use in an application like this. The only problem is that they use an SPI bus. This bus has more wires than the calc does so once again another chip will be needed externally. If you got an EEPROM that was sufficiently large and that used the Philips I2C bus then you could do something like this with only a calculator and power source. The EEPROMs that I have seen to this date do not get as large as I would like to consider doing this as a project.

I am confused, why would an mp3 mass storage device not work? All you should have to do is make an on calc program, no? And if not, why not?

-W-

Because if the way the USB hardware works. When you use the good old unit-to-unit cable, all you're really doing is connecting three wires of one calc to three wires of another calc. Once the wires are hooked up, TI-OS can start sending and receiving data.
With USB however, connecting the wires isn't sufficient; USB needs a root hub to work. Now the problem is that the calc doesn't have a root hub. Therefore it is not possible (on the hardware level) to connect an USB stick to the calc.

Where can I find more information about USB hardware and what it takes to connect a device to another.

Would the TI-89 titanium be able to use a USB memory-expansion device? It has a built-in USB port. . .

Hey, I know I'm reviving an old thread, but the new site is down too. Does anyone have the plans for the Expander II anymore? I would appreciate them very much.

What sbout the firmware chip? His site says to contact him, but he is having no more to do with the project… .

He also says on his site that all the super large font is content has only recently added. Meaning that where it says to contact him was what he wrote a long time ago.

That's what I mean. He said to get it from him a ling time ago. Can we still??

Is he making avaliable the code for the firmware, or is that something that we must all figure out?

The web link on this msg is the E2 AVR code. You can compile it and program the chip with tools from atmel.com or, in Linux, search freshmeat.net for AVR and/or google "avra"

Google "ba1fb" for cheap AVR programmer hardware.

-Bryan

Firmware chip?

I'm pretty sure you just need a PIC chip, a PIC programmer interface, and te necessary I/O program(s)...

The Atmel AVR is a different chip than the PIC, but they are both low end microcontrollers. It'd be fairly simple to port the code to a PIC I'm sure.

was there an expander I? I can find no mention of this on the website.

Most likely an earlier version of the same project.

FYI, to those of you interested in porting the "software" to other calculators the source code is available for all three caclulators on his author profile page linked in the article.

OK kids its story time. ;-)

The original TI expander was called the Expander SF (Serial Flash) and was built by Mel Tsai. It was essentially just a serial memory chip connected directly to the TI link port. Supply dried up for the ESF chip and Mel moved on to other projects, so I built the Expander2 to scratch an itch. Mel's design was only for the TI-85 whereas the E2 grew to work on TI-85, TI-86 and TI-92.

I guess the E2 is now kind of like the ESF. The flash memory chip for it has also been discontinued. I'm hoping someone comes along and builds the E3 perhaps based on the old plans from my site.

-Bryan

ooh, ooh, tell me another one! Pretty please...

Here's my question: because it works on the 92, does that mean it works on a 92+? And if it were to work on a 92+, would it work on a V200?

No, the program used on the 92 requires Fargo, a shell that was never used with the 92+. You would think it would be fairly simple to port it, but I could be wrong.

There's always this...

http://www.angelfire.com/ electronic2/ngdata/programing/ en/ti89/ticfrw.html

(Remove spaces, as always.)

why did you put spaces in if you are just gana get rid of them???

cause you can't post links on these forums.

Precisely. And it was just a tad too long to put it in the "(Web Page)" spot.

what would happen if u just typed it in here as normal text?
Example: www.coolcals.tk (shamless plug)

There is a 40 character word limit. Thas the only rule. There isn't a rule that says you can't post URL's. its just that most of them are over 40 characters.

Bryan,
I was one of probably only a few people who successfully built and used the original memory expander device, from Mel. Have you heard of anyone making development on it's driver? It was an amazing device, and I know yours is too. As you point on your page, memory has moved along so much, no flash isn't a stranger anymore. We use it every day. At that time, it was practically brand new.