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misch
Hey eveybody:

I have a SL-5500 and now a C3000. I managed to get my AUDIOVOX
GPRS card to run on the Sl-5500 by replacing the serial_cs.o module.

On the C3000, serial_cs is compiled into the kernel - but I managed
to adapt the serial_cs module and to recompile the kernel.

The modem is now initialized and able to connect to T-Mobile's GPRS
network. So far, so good.

I haven't been able to get any useful data over the network. This
os how my ifconfig looks like:

UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
Rx packets: 16 errors: 65 dropped: 0 overruns:0 frame:0
Tx packets: 85 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:3
RX bytes: 552 (552.0 b) TX bytes:5977 (5.8Kb)

The error-counter seems to be the problem. Somehow, most data-packages
get whacked somewhere. But .. where?

This is what I tried so far:

Original kernel: Is not able to initialize modem
serial_cs.c from vanilla 2.4.27: compiled as module: Connects, lots of errors.
serial_cs.c from vanilla 2.4.27: compiled in to kernel: Same
serial_cs from Sharp Kernel, patched, as module: Same
serial_cs from Sharp Kernel, patched, compiled into kernel: Same

Change mtu's / mru's and a lot of other ppp options, with or without
compression, whatever, result is the same.
I modified /etc/pcmcia/serial.opts with UART and without: same
Change baudrates in ppp script: same

No messages of any specific meaning in regard to that problem from
syslog (yep - I changed configuration accordingly)

I 've started to look for ghosts now :) Any other suggestions?

Michaela
misch
Update:

Added DEFLATE Option in kernel: No change

Pinging (any) IP-address looks like this

PING www.spiegel.de (195.71.11.67)
64 bytes from 195.71.11.67: icmp_seq=7 ttl=237 time=822.6ms
64 bytes from 195.71.11.67: icmp_seq=8 ttl=237 time=912.6ms
64 bytes from 195.71.11.67: icmp_seq=13 ttl=237 time=788.5ms
64 bytes from 195.71.11.67: icmp_seq=21 ttl=237 time=1104.2ms
64 bytes from 195.71.11.67: icmp_seq=22 ttl=237 time=711.1ms
64 bytes from 195.71.11.67: icmp_seq=29 ttl=237 time=855.2ms

etc ..


Wireless with a AmbiCom wireless card works flawlessly.
misch
Update II:

Just brought my SL-5500 to a new life. Of course batteries dead and I had
to install my usual tools first. It connected to the GPRS with no problems
and data-transmission was just fine. I used the ppp-scripts from the C3000
to be sure, it's not a script issue.

ifconfig and netstat on the SL-5500 looked ok (no errors) and the routes
are exactly the way they are on the C3000.

I than copied the pppd binary from the SL-5500 to the C3000 and retried.
Guess what: Same problem: A connect, but not usable data transfer (rx
error counter going up).

If its not a script issue, if it is not the pppd, the modem or the provider, that
leaves me with no other choice than the kernel ? Damn.
misch
Update III

Went back into the serial_cs Kernel source. Everything seems to be
fine:

kernel reports: ttyS03 at port 0xf60003f8 (irq=135) is a 16C950/954

I am more used to IRQs in the range of 35 though, but read on ..
setserial says: /dev/ttyS3, UART 16550A, Port 0xf60003f8, IRQ: 135

Everything ok.

cat /proc/interrupts gives me a 135: 172 Serial

as soon as I start to play around with the modem. So, interrupts are
assigned and are responding to the card. But why the hell am I not
getting any useable data over this port .. ?
misch
Update IV

Patched kernel-ppp.c to show what is wrong with the incoming
packages. Well, almost all packages come with bad FCS (Frame
Check Sequence), that means the data packet got corrupted
somweher in the serial chain. And I mean almost _all_ (> 90%) of
them are bad.

Change the baudrate from 115200 to 57600, no effect. Replaced
the kernel-serial.c with a version from a sl-5500 kernel, no
effect.

I even slipped the modem-card back into the sl5500 (worked
instantly) and hold the antenna close to the C3000 (I thought
there might be some interference from the C3000) but the
connection continued to work well in the sl5500.

Conclusion: I have not the slidest idea what the hell is going
on. I know, the scripts are ok, the modem is ok, the provider
works well (all tested with the SL5500), I replaced serial_cs.c
with different versions from different Zaurus and Vanilla kernels,
I replaced serial.c with other Zaurus und vanilla versions, all
to no avail. I tried a different pppd - all gives me the same
result. The only difference is the interrupt, the modem card
is assigned to : On the SL5500 it's IRQ35, on the C3000 its
IRQ 135 (even though that does not seem to be a problem,
see Update III).

I need that modem running. After all, what is a pda good for
if you can't take it outside and still keep connected .. ?
misch
SOLVED:

I got it: After lots and lots of research, I finally found the solution.

You have to add the following to /etc/pcmcia/serial

echo 1 > /proc/lock_fcs

into the resume section and the corresponding

echo 0 > /proc/lock_fcs

into the suspend and stop sections

Works flawlessly now. I am *happy*
MRNUTTY
misch: i have an c3000 and the Audiovox GPRS card, but i'm quite baffled how to get even as far as your first post. my WIFI card configured through the network configuration wizard ok, but i don't know how to get this card recognized. any help please?
Thanks!
misch
QUOTE(MRNUTTY @ Feb 18 2005, 06:35 PM)
misch: i have an c3000 and the Audiovox GPRS card, but i'm quite baffled how to get even as far as your first post. my WIFI card configured through the network configuration wizard ok, but i don't know how to get this card recognized. any help please?
Thanks!
*


Go to www.steyla.com, scroll al the way to the bottom, click on special on zaurus computers, then click on 'Connect an Audiovox GPRS modem to a C-3000'

Feel free to contact me, if you can't get it running now.

mm.
MRNUTTY
QUOTE(misch @ Mar 4 2005, 02:18 AM)
QUOTE(MRNUTTY @ Feb 18 2005, 06:35 PM)
misch: i have an c3000 and the Audiovox GPRS card, but i'm quite baffled how to get even as far as your first post. my WIFI card configured through the network configuration wizard ok, but i don't know how to get this card recognized. any help please?
Thanks!
*


Go to www.steyla.com, scroll al the way to the bottom, click on special on zaurus computers, then click on 'Connect an Audiovox GPRS modem to a C-3000'

Feel free to contact me, if you can't get it running now.

mm.
*



Jeepers! i thought i responded to this smile.gif thanks to your instructions i've been GPRS-ing for a couple of weeks! IT'S great!!!!!!

Thanks!!
John
Bombur
Misch,

I just obtained a Treo 650 and the BT DUN was not working worth a sh*t. Then I remembered this post and lo and behold the BT DUN started working! Funny thing is, the BT DUN on my T637 worked just fine. I never would have figured this out.

Thanks a lot for your perseverence.

J.
vc24
Nice job, misch! I've just tried Pretec GPRS CF card and it works perfectly after applying all your hints. Thanks a lot!
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