Re: [jornada] de-brick

* Jamey Hicks <jamey.hicks@hp.com> [021009 18:28]:

>>>The intermittent nature of the problem with JTAG makes me think it is a
>>>signal integrity problem. I have run into the same thing here on
>>>occasion. If you soldered connections, make sure none are cold solder

>>Yes, I did solder them and that's the first thing I checked. The signals
>>seem to be well separated from each other.

>There are two things that are important here. First, that the wires are
>not shorted together. Second, that there is a good solid connection for
>each wire.

I think there is. This is rather subjective though.

>I would also recommend making the wires as short as possible.

I'll do that right now, I'm at home already :)

>>Oh, I definately can do that. Now that I think of it, that might well be
>>the problem since I am using 2 meter 1-wire cables for it. That, and
>>making sure all the resistors I bought are really giving the same
>>resistance, which I did not check, are the two things I'll do when I get
>>home, which will be in about 3 hours and a half from now :)

>The value of the resistors is not important. The resistors are there to
>prevent ringing on the jtag signals. However, such long wires can cause
>noise on the signals, so if you still have problems I recommend
>shortening it to a half meter or so.

I guess 2 meters is really a bit on the long side.

>>BTW, is the binary
>>ftp://ftp.handhelds.org/feeds/bootldr/bootldr-2.19.30.bin
>>supposed to work with the Jornada? Or do I need to recompile it
>>specifically for the 56x?
>>
>That one has not been tested with the jornada. We'd like you to test
>it, but John has one he knows works, and the URL is:
> ftp://salsa.lcs.mit.edu/pub/jca/b560

All right, I'll try both if jflash gets to work reliably.

>>And if I succesfully load the bootldr, will I need a serial connection?
>>Or is there any way I can get linux installed by using only the JTAG
>>and USB port? I had successfully used the Jornada through the USB port
>>under Linux with WindowsCE on the PDA, if that's of any relevance until
>>it is a fully linux machine :)
>>
>You will need a serial connection to use the bootldr to install linux in
>flash.

Do you know anywhere where I can find some schemes to do my own adaptor?
Since I'll only be using it to install linux, I prefer not spending the
amount they ask for an HP branded original cable.

-- 
Javier Marcet <jmarcet@pobox.com>
Saint Louis University, Madrid Campus