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[geep]

Hi everybody,
Not a problem, but curious about a change in my DSL connection...

Downstream my ST546 usually shows lots of FEC errors which increase steadily, a lesser, but increasing, number of CRC errors and some HEC errors. The router is on 24/7 and resyncs periodically, usually every day or so.

It resynced a couple of hours ago and now isn't showing any FEC errors, but CRC and HEC are steadily increasing.
http://www.kitz.co.uk/adsl/linestats_errors.htm says:

"FEC ... Error correction is turned on at the same time as Interleaving".

So should I assume that BT (or my ISP?) have suddenly decided to switch off interleaving?

Does anybody know a command to interrogate the ST546 for the interleave status?
I have the Thomson ST516/536/546 CLI Reference Guide.
It has an example of the command "adsl info"  showing "Channel Mode : interleaved". But on mine it just says:

Code: [Select]

{Administrator}=>adsl info
Modemstate                   :  Up
xDSL Type                    :  ADSL2+
Bandwidth (Down/Up - kbit/s) :  8494/904
Uptime (days hh:mm:ss)       :  0 days, 2:48:41
I think I have the crippled firmware: Software Release:   6.2.17.5.
Don't want to change the firmware as had enough hassle setting it up the first time.

Cheers,
Peter

Current values:

Code: [Select]

Link Information
Uptime: 0 days, 2:58:51
Modulation: G.992.5 annex A
Bandwidth (Up/Down) [kbps/kbps]: 904 / 8,494
Data Transferred (Sent/Received) [KB/KB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.5 / 21.5
Line Attenuation (Up/Down) [dB]: 20.5 / 37.5
SN Margin (Up/Down) [dB]: 6.5 / 6.0
Vendor ID (Local/Remote): TMMB / TSTC
Loss of Framing (Local/Remote): 0 / 0
Loss of Signal (Local/Remote): 7 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 42,140 / 0
FEC Errors (Up/Down): 9,262,239 / 0
CRC Errors (Up/Down): 329,586 / 37,362
HEC Errors (Up/Down): 616,454 / 15,286Yes - I know the upstream error values are crazy. I'm sure I've seen this discussed elsewhere in the forum but can't find it at present. Seems it's a feature of the ST546, the upstream errors are never reset to 0.

[kitz]

The upstream error figures are sometimes retained by the dslam/msan.   
This is something I observed a while back..  I spend ages unsucessfully trying to find a way to clear them, but couldnt.  It was only when I swapped out the ST for a DG834GT and  the figures has followed to that... when I realised that it had to be the MSAN.  It does sometimes reset, but Ive not found a pattern to it.


The CLI should show interleaved or FAST somewhere..

_{Administrator}=>adsl info
Modemstate            :  up
Operation Mode        :  G.992.5 Annex M US 56
Channel Mode          :  interleaved

So maybe its that particular firmware version:/

Try putting DMTtool on and then running through the commands under the 2nd tab [Info2]

try things like
adsl info expand=enabled
debug exec cmd='tdsl getData all'


BTW.... That line is working really hard atm - 21.5dB output power!

[geep]

Thanks,
I have tried most of the likely commands from DMTv7. Didn't see any sign of anything about interleaving or FAST. Quite  a number of the commands don't work - not recognised. DMT only displays the Bitloading graph, the other two are blank. For the two commands you suggested:
1/

Code: [Select]

_{Administrator}=>debug exec cmd='tdsl getData all'
=====================DISCLAIMER======================
 Access to expert commands is intended for qualified
 personnel only.
==================END=OF=DISCLAIMER==================
Command not allowed2/ adsl info expand=enabled - already using this command in Perl monitoring script based on http://tinyurl.com/y8oqurc
Nothing about interleaving or FAST in the output that I can see. But I know I need new specs.

Code: [Select]

_{Administrator}=>adsl info expand=enabled                              

Modemstate                   :  Up
xDSL Type                    :  ADSL2+
xDSL Standard                :  ITU-T G.992.5
xDSL Annex                   :  Annex A      
Uptime (days hh:mm:ss)       :  0 days, 0:09:42

Number of resets             :  1

Total Available Bandwidth           Cells/s           kbit/s
  Downstream                 :     20051             8502    
  Upstream                   :      2113              896    

Intrinsic/Actual and Maximum Bandwidth %              kbit/s
  Downstream                 :       107             7908  
  Upstream                   :         4            18679  

Bearer Generic Info               Downstream        Upstream
INP          (DMT)           :         0.00             0.00
Delay        (ms)            :         0.23             1.00
R                            :         0                0    
Margin       (dB)            :         6.0              6.5  
Attenuation  (dB)            :        37.5             20.5  
OutputPower  (dBm)           :        21.5             12.5  

Vendor Chipset                      Local            Remote
  Country                    :        B5               B5  
  Vendor                     :      BDCM             TSTC  
  VendorSpecific             :      0000             0005  
  StandardRevisionNr         :        00               02  
Vendor System                                              
  Country                    :        0F               00  
  Vendor                     :      TMMB             ----  
  VendorSpecific             :      3C61             0000  
  StandardRevisionNr         :        00               00  


Transfer statistics
    Errors        
      Received FEC           :         0
      Received CRC           :        58
      Received HEC           :        20
      Transmitted FEC        :   9262239
      Transmitted CRC        :    330044
      Transmitted HEC        :    616606

     Near end failures since reset
      Loss of frame          :         0 failures
      Loss of signal         :         0 failures
      Loss of power          :         0 failures
      Errored seconds        :        10 seconds

     Near end failures last 15 minutes
      Loss of frame          :         0 seconds
      Loss of signal         :         0 seconds
      Loss of power          :         0 seconds
      Errored seconds        :        10 seconds

     Near end failures current day
      Errored seconds        :        10 seconds

     Near end failures previous day
      Errored seconds        :         0 seconds
One of the commands from DMT must have upset the router. It disconnected from the Internet and ST546's Connectivity Check web interface reported DSL - OK, ATM - could not send loopback cell, PPP - your connection is currently down. Fortunately it has restarted OK.

Cheers,
Peter

[orainsear]

Fastpath or Interleaved is usually shown just above the graph section of DMTtool.  The status should be displayed directly to the right of the globe icon.

[geep]

Unfortunately not for me. Seems the later firmware doesn't support the interesting stuff.


http://pgg999.co.uk/stats/images/st546.bitspertone.3d.jpg
Cheers,
Peter

Edit - Saturday 3 Oct - router resynced itself this morning and FECs are back again.
Yesterday evening had to manually resync as the evening noise took the margin down to about 4.5dB and the CRC error rate shot up making performance intolerable. 

[orainsear]

You're probably correct about it being the 6.2.x firmware that's causing the issue.

Changing the firmware may be the only option.

I've experienced issues in the past when changing the firmware on Speedtouch devices, however they have generally been when trying to downgrade, upgrading always seemed to go fairly well.