2 Io Questions

[EvilDragon]

Hi,

I have to small IO questions to you experts

1. Max (from Dreamcast-Scene) wants to built a DC <> gp2x Link cable.
Can anyone tell me the pinouts for the ext. Port? Thanks

2. As there exist a few brick tools (PSP, NDS), some people are a bit afraid of homebrew.
That's why I want to offer free reflashing of the gp2x Firmware at my shop.
Can anybody of you tell me if this is possible (using JTAG cable, serial cable, etc.)?
And what would I need to do it?

Thanks a bunch

 

[Squidge]

We don't have much information on the EXT port, but we can certainly tell you where one of the UARTs come from if you want to use that.

If uboot is still present, you can reflash using a serial cable, otherwise you will have to use a jtag lead. JTAG pinouts are on the serial adaptors the devs use with the dev boards, so should be quite easy to make up.

 

[EvilDragon]

Well, I don't need it yet, but if there is definately a way to reflash the gp2x (I saw DJWillis having some problems with the reflash here), even if I have to built a JTAG cable, that's good.

 

[DJWillis]

Well, I don't need it yet, but if there is definately a way to reflash the gp2x (I saw DJWillis having some problems with the reflash here), even if I have to built a JTAG cable, that's good.

​

They can be returned from flash death . A serial and jTAG are your friends but it's not hard. Serial is SLOW however and I suspect jTAG is also damm slow.

What really worries me is that brinking the unit is not hard at all. Linux is actualy very fragile if you do something a bit stupid (and a lot of people will do just that) .

 

[EvilDragon]

Well, I don't need it yet, but if there is definately a way to reflash the gp2x (I saw DJWillis having some problems with the reflash here), even if I have to built a JTAG cable, that's good.

​

They can be returned from flash death . A serial and jTAG are your friends but it's not hard. Serial is SLOW however and I suspect jTAG is also damm slow.

Well, that doesn't matter, as long as I can offer a recovering service

What really worries me is that brinking the unit is not hard at all. Linux is actualy very fragile if you do something a bit stupid (and a lot of people will do just that) .

​

Oh... how easy is it?
Can you just open up a filemanager and delete the kernel image, for example?

 

[DJWillis]

Oh... how easy is it?
Can you just open up a filemanager and delete the kernel image, for example?

​

Yep, as it stands you could pull a few key files off the NAND disk iamge and it would not boot, with the console output sent to the serial port you would have no idea what went 'bork!' so despite it being an easy fix Joe Public would see it as bricked.

 

[EvilDragon]

Oh... how easy is it?
Can you just open up a filemanager and delete the kernel image, for example?

​

Yep, as it stands you could pull a few key files off the NAND disk iamge and it would not boot, with the console output sent to the serial port you would have no idea what went 'bork!' so despite it being an easy fix Joe Public would see it as bricked.

​

Oh, geez... so we REALLY have to tell the folks Shells and File Managers are EVIL if you mess around with your NAND...

Wouldn't it be possible protecting the boot area?
I mean, if the standard GUI uses a non-root-account, it should be...

 

[DJWillis]

I mean, if the standard GUI uses a non-root-account, it should be...

​

:lol: :lol: :lol:

Sorry, a secure non root account . Hmmmm, who would have thought of that little gem of an idea, not GPH for sure.

Nope, all the user-space stuff seems to be running under root. I don't think it would be hard to change, but then as soon as the root password became known any bricking app could just SU .

 

[Squidge]

Well, I don't know about the "final retail" version, but the current version I have, the storage area for user stuff, and the area for the os is the same partition. Since the os writes to it's area on bootup, if you store too much stuff so the OS can't write it's temp files on bootup, you'll get InstaBrick status :-/

Considering that only 24MB of the 64MB of flash is used at the moment, hopefully they'll make use of the free space for user stuff, instead of sticking it in with all the OS files. Maybe then, /tmp can be moved to the user partition, and the rootfs can be mounted read-only. Should offer a little protection against people & file managers at least.