[LinuxBIOS] #57: libusb host program for PLX NET20DC debug device
Eric W. Biederman
ebiederm at xmission.com
Mon Dec 4 00:03:55 CET 2006
Peter Stuge <stuge-linuxbios at cdy.org> writes:
> On Fri, Dec 01, 2006 at 04:02:03PM -0700, Eric W. Biederman wrote:
>> >> Sure, I will send it out shortly. I currently have a working
>> >> user space libusb thing (easy, but useful for my debug)
>> > Hm - for driving which end?
>> Either. The specific device we are talking about doesn't care.
> Which device do you have?
Well it is built by PLX, and from lsusb I see are:
0525:127a Netchip Technology, Inc.
The hardware is a little rectangular pcb board a little smaller
then a business card. Wrapped in a blue case, with vertical vents
on both of the long sides, and gets a little warm when you have been
running it for a while. The device has what appears to be 2 normal
host to slave cables running into it.
The picture at the bottom of:
Looks like what I have. I'm curious about the whole plug both
ends into the host before plugging it into the client, and about
the strange target system BIOS requirements.
I think I succeeded in making it work without out that by just putting
in a reset. It does make the whole setup of the device a pain though.
>> > The debug port isn't really supposed to be used with anything but
>> > a debug device - which can't be enumerated normally anyway.
>> It depends. If you have a debug cable with magic ends and a
>> hardcoded address of 127 the normal enumeration doesn't work. I
>> don't think anyone actually makes one of those.
> Only one of the ports on Stefan's PLX NET20DC that I had a look at
> during the LinuxBIOS symposium enumerated for me.
Very odd. I'm pretty certain we are talking same thing. But I do
know it has a couple of weird quirks, so maybe you just ran up against
>> Debug devices are also allowed to be normal devices that just
>> support the debug descriptor. Which is what I'm working with.
> Aye. I would be happy if we could get something out, as you have
> done! :) Looking forward to trying it, I hope I get my device soon.
Well at least this means after it works I can probably forget about
it and let someone else maintain the code ;)
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