Crazy idea: CE 4.2 on a Jornada 728?

That'd be me. Check out the first post on page three of this thread. No reply was received, but the parts can be sourced other places, they just require a larger quantity be ordered. Google the part number. It's doable.

Right a quick update before more info is available:

There is no JTAG interface on the 720/728 board, so the chips would have to be programmed some other way before they were soldered on. I really don't like the idea of trying to unsolder/resolder SMT flash roms but if you think it's not an issue, go for it.

The replacement flashboard design project is currently sleeping due to Mark being busy with work, however his contract finishes next week so there's a chance that, with enough interest, he could re-open it. The design would be a full replacement ROM board, complete with RAM. There would be a protected bootloader on the board which would allow for on-device flashing of the ROM, however in the event of a total screwup the bootloader should always work allowing restore by some mechanism or other without hardware. The bootloader would have to be initially programmed outside of the device, so development of a programmer is necessary - although not complex

Mark has around 25 names for this already. If we could give volume to him, it would change the price considerably (target price is currently $100 or thereabouts).

This project was started as a way to get Linux on the machine, but with a flashable ROM it gives anyone the option to do anything they want.

I'm awaiting a response to a couple of questions, then we'll probably start a new thread in general as this could be more interesting for the Linux folks , given that they have an OS ready to rock on this boad already, but it is a means to an end for the 4.2 dream...

I sent Mark a letter of interest and encouragement. I recommend anyone and everyone interested do the same.

chiark, thank you, sir, for taking this on.

Edited by oflash 2006-11-06 3:07 PM

hey, I'm not taking anything on: I'm carefully not promising anything . I think that the weight of numbers of people wanting a flashboard for WinCE .net 4.2 pooled with people who want one for Linux will help.

Now, who can think about making this work from a bootloader then???

actually I really can't understand why we can't boot CE4.2 from a bootloader like we did with linux...

because we don't have a 4.2 image that works with the 720 hardware.

So who has the skills necessary to correct that?

any way you could pull the needed drivers from the '72(0/8) and edit them for use with 4.2?

silly, masked rom in 2006?! it *has* to be flash. i'm not buying if it is not flash if the bootloader is protected then no risk.
flash enables to create updates, correct errors, add new things and flash them in. you can choose between cenet and linux at will.. no i wouldn't want to give up this freedom!

anyway, i read all posts, interesting stuff, sounds nice! i'm willing to try build a cenet image but i don't know if every driver will be available in PB.. will probably need help with that..
anyone ever played with PB before? would be better to have more than one person working on this

I played around with platform builder. It has the drivers for pretty well nothing. It's not just a matter of clicking a few buttons and compiling the image.
There's also the matter of software which doesn't fit on the Jornada's screen.

well, it has a lot of drivers for various video chips.

screen res won't be a problem, if NEC could adjust the programs for the 900 we can do the same.

i never said it would be just a couple of clicks rofl

I don't have nearly enough time in my life to play with PB - see the "new member" thread

I think we should probably start another thread for the flash board interest...

I meant it lacks drivers useful to the Jornada, as near as I can tell.
Rearranging all the programs shouldn't be impossible, just interesting.

I'd be really interested in a flash board. Especially with 128Mb of RAM..

look, I think that a bootloader will be for sure the easiest way to start with that. Since we got the 4.2 image running fine on bootloader, we can then put it into flash boards. But anyway I don't think that will be wise to do that, specially about putting 128MB of RAM on it, first because it's extremally hard, and second because RAM means Energy. Then, more RAM do you have, more energy is necessary to keep the PDA working in sleep mode, and less battery time you get. I think really that the best solution is start looking for drivers to work with jornada. What about some generic "VESA" driver for 640x240, do we have it? Maybe getting video to work, sound will not be the worst problem...

oh don't worry about the power consumption. the jornada 728 can last quite a few weeks (over 1 month i think, with its 1960 mAh battery though) and it is already 64mb. if 128 halves that it'll still be very decent.