Work at SourceForge, help us to make it a better place! We have an immediate need for a Support Technician in our San Francisco or Denver office.

Close

#21 DS2490 problems

open
Paul Alfille
owhttpd (3)
5
2012-09-14
2006-07-03
Claes
No

Dear all

I'm still having problems getting my DS2490 interface
to work properly with my Linux box.

The problem was described earlier in the port "Debug
questions" and the problem is that devices on the bus
disappears and also fails to read values randomly. When
this happens I get a lot of BUS_read_error,
BUS_select_low and BUS_CRC errors in the statistics
section and the debug output shows the following when
an error occurs:

DATA: DS9490_reset
DATA: DS9490_reset: ok
DATA: DS9490_read: failed ret=0
CONNECT: SELECTION ERROR

When it looked like this might be an electrical problem
on the 1-wire bus I tried a lot of things including RC
filers and resistors to reduce echo’s, --altUSB switch
for USB timings etc. but there were no improvements. I
also tried the DSL CD provided on several different PC
HW, but with the same problem (DSL also have a 2.6
kernel). When Vincent suggested this might be Linux
kernel related I installed the OW development kit
provided by Dallas on my WinXP PC (AMD X2 3800+) and
was very surprised to see that it worked perfectly (no
errors, missing devices and correct values read every
poll which was 1 second). I just assume this would rule
out any 1-wire bus electrical problems.

I would however really like to use OWFS on my Linux
box, but downgrading to kernel 2.4 is not an option as
I have other things running which require 2.6.

Some more info:

My Linux version is Mandriva 2006 (clean install from
CD) running default kernel 2.6.12-12, using FUSE 2.5.3
(downloaded & compiled), default libusb 0.1.4 (came
with dist), owfs 2.4p3 compiled and installed without
errors (also tested 2.4p1 and p2).

The Linux HW is an EPIA Via V10000 ITX board with a
1GHz EDEN CPU, 512Mb memory etc., however as I tested
on other HW with same problem I don’t think it is a HW
issue and the CPU performance should be enough I think.

Help! Does anyone have any ideas on what might be wrong
here?

Best Regards
/Claes Martinsson

Discussion

  • Claes
    Claes
    2006-07-04

    Debug output

     
    Attachments
  • Claes
    Claes
    2006-07-04

    Picture of statistics/errors

     
    Attachments
  • Claes
    Claes
    2006-07-04

    Logged In: YES
    user_id=1549120

    Deal all

    I added two attachments to this case. One being an
    extensive debug output and the other a picture of the eror
    statistics.

    With regards to the binaries I did compile the 2.4p3 source
    code and installed from scratch (no RPM installation). Did
    the same with FUSE (had to compile the kernel again for
    this). I did remove the fuse and DS9490 kernel modules that
    came with the distribution to avoid conflicts.
    The DSL I refered to was the ISO image DSL on the OWFS
    download page. If I don't remember wrong this was running
    kernel 2.6.

    Unfortunately I'm not good at reading the debug output so I
    would appreciate your expertese to see if you can find the
    root cause of the problems.

    As always big thanks for all your support.

    Best Regards
    /Claes