[Asterisk-Users] spandsp with TDM fxo card?

[Rich Adamson]

Hi Steve,

Thanks for the reply. Questions below...

> Most of my testing, while developing spandsp, has been with connections 
> through a Digium E1 card, and with FAX machines plugged straight into a 
> TDM40P. I have used an X100P a few times to receive FAXes over the PSTN, 
> but I haven't used that confiuration extensively. It certainly can work.
> 
> Regards,
> Steve
> 
> 
> Rich Adamson wrote:
> 
> >Has anyone made spandsp to work with a digium tdm fxo card?
> >
> >I finally got the rxfax and txfax modules to compile, the spandsp lib
> >installed (and in the libpath), and now receive:
> >
> >    -- Starting simple switch on 'Zap/1-1'
> >    -- Executing RxFAX("Zap/1-1", "/var/fax.tif") in new stack
> >    -- Hungup 'Zap/1-1'
> >
> >I've tried to adjust rxgain/txgain in zapta.conf, but never get to a 
> >point of receiving anything more then the above at the cli. The
> >fax machine is an older Brother unit.

In running * in cli debug mode, I get the following. Need a little
help decoding the messages as I'm not sure what's going on here.
I've inserted some comments beginning with <=== below. (This is
based on an older Brother MFC-1770 initiating the fax to asterisk.

Sep 26 17:36:27 NOTICE[1116363568]: chan_zap.c:5340 ss_thread: Got event 2 (Ring
/Answered)...
Changed from phase 0 to 1
Urgent handler
Urgent handler
Urgent handler
Start receiving document
Changed from phase 1 to 4
Sending ident
>>> CSI: 40 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
DIS:
Preferred octets: 256
Can receive fax
Supported data signalling rates: V.27ter and V.29
R8x7.7lines/mm and/or 200x200pels/25.4mm OK
2D coding OK
Scan line length: 215mm
Recording length: A4 (297mm)
Receiver's minimum scan line time: 0ms at 3.85 l/mm: T7.7 = T3.85
R8x15.4lines/mm OK
Minimum scan line time for higher resolutions: T15.4 = T7.7
>>> DIS: 80 00 ce f0 80 80 01
Urgent handler
Urgent handler
HDLC underflow in state 9  <=== What does this mean?
Changed from phase 4 to 3
Slow carrier up
<<< TSI: 43 30 38 33 31 34 36 34 32 30 34 20 20 20 20 20 20 20 20 20 20
TSI without final frame tag
Remote fax gave TSI as: "4024641380"  <=== this is correct.
T4 timeout in state 9
Changed from phase 3 to 4
Sending ident
>>> CSI: 40 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
DIS:
Preferred octets: 256
Can receive fax
Supported data signalling rates: V.27ter and V.29
R8x7.7lines/mm and/or 200x200pels/25.4mm OK
2D coding OK
Scan line length: 215mm
Recording length: A4 (297mm)
Receiver's minimum scan line time: 0ms at 3.85 l/mm: T7.7 = T3.85
R8x15.4lines/mm OK
Minimum scan line time for higher resolutions: T15.4 = T7.7
>>> DIS: 80 00 ce f0 80 80 01
HDLC underflow in state 9
Changed from phase 4 to 3
Slow carrier up
Slow carrier down
Slow carrier up
T4 timeout in state 9
Changed from phase 3 to 4
Sending ident
>>> CSI: 40 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
DIS:
Preferred octets: 256
Can receive fax
Supported data signalling rates: V.27ter and V.29
R8x7.7lines/mm and/or 200x200pels/25.4mm OK
2D coding OK
Scan line length: 215mm
Recording length: A4 (297mm)
Receiver's minimum scan line time: 0ms at 3.85 l/mm: T7.7 = T3.85
R8x15.4lines/mm OK
Minimum scan line time for higher resolutions: T15.4 = T7.7
>>> DIS: 80 00 ce f0 80 80 01
HDLC underflow in state 9
Changed from phase 4 to 3
Slow carrier up
Slow carrier down
Slow carrier up
Slow carrier down
<snip>
Slow carrier up
Slow carrier down
Slow carrier up
Slow carrier down
T4 timeout in state 9
>>> CSI: 40 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
Sending ident
>>> CSI: 40 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
DIS:
Preferred octets: 256
Can receive fax
Supported data signalling rates: V.27ter and V.29
R8x7.7lines/mm and/or 200x200pels/25.4mm OK
2D coding OK
Scan line length: 215mm
Recording length: A4 (297mm)
Receiver's minimum scan line time: 0ms at 3.85 l/mm: T7.7 = T3.85
R8x15.4lines/mm OK
Minimum scan line time for higher resolutions: T15.4 = T7.7
>>> DIS: 80 00 ce f0 80 80 01
HDLC underflow in state 9
Changed from phase 4 to 3
Slow carrier up
<<< TSI: 43 30 38 33 31 34 36 34 32 30 34 20 20 20 20 20 20 20 20 20 20 <=== this is the 
fax machines number in reverse order.

TSI without final frame tag
Remote fax gave TSI as: "4024641380"  <=== correct
<<< DCS: 83 00 06 a0 80 80 00
DCS with final frame tag
In state 9
DCS:
Can receive fax
Selected data signalling rate: V.29, 9600bps
Scan line length: 215mm
Recording length: A4 (297mm)
Minimum scan line time: 10ms
Minimum scan line time for higher resolutions: T15.4 = T7.7
Get at 9600
Changed from phase 3 to 5
Fast carrier up
Coarse carrier frequency 1702.12 (6)
Training error 714.707083
Training failed (convergence failed)  <=== what's this?
Fast carrier training failed
Fast carrier down
Fast carrier up
Fast carrier down
Fast carrier up
Fast carrier down
Fast carrier up
Fast carrier down
Fast carrier up
Coarse carrier frequency 1782.75 (6)
Fast carrier down
Fast carrier up
Coarse carrier frequency 1789.40 (4)
Training error 676.749259
Training failed (convergence failed)
Fast carrier training failed
    -- Hungup 'Zap/1-1'  <=== fax machine or channel hung up

In making several runs at this (with varying rxgain/txgain settings),
I notice the frequency entries above vary rather widely. I'm suspecting
a motherboard irq/pci controller issue might be lurking (this same *
machine does have an echo issue, and Mark's echotraining=800 fix from
around June 2004 pretty much corrected it).

Can you suggest any other items that might be cause this to fair. 
There never is a /var/fax.tif file created since I'm assuming the
training/negotiation is failing way before receiving any real fax
data.

Rich