[Soekris] Digium TDM400P (2 FXS, 2 FXO) on net5501

[Graham Freeman]

Hi, folks,

First of all, I'd like to extend my hearty thanks to Soekris  
Engineering for producing an excellent product line.  I've deployed  
net4501- and net4801- based firewall/VPN endpoints (mostly running  
m0n0wall[1]) for a number of clients, and the results have been truly  
excellent.  Sturdy, reliable, and powerful enough to do the job.

So, in the process of experimenting with VOIP I'm getting my hands  
dirty with various distributions of Asterisk on various hardware  
configurations.   For my own home office PBX, the Soekris net5501  
seems to be the best fit - it makes no noise whatsoever, is  
physically small, consumes very little power, seems to be powerful  
enough for my needs, and has room for an FXS/FXO[2] adapter card.    
Best of all, AskoziaPBX[3] is rapidly shaping up to be an excellent  
Asterisk implementation well-suited to the net5501, much in the same  
way that m0n0wall is an excellent firewall/VPN endpoint.

Here's my question:  Will the Digium TDM400P[4] (with 2ea S110M FXS 
[5] and X100M FXO[6] modules) work in my net5501?  If so, will I need  
a supplemental power supply such as the Digium PWR2400B[7]?  If so,  
any suggestions on how I'd shoe-horn it into the case after  
installing the TDM400P?

I saw the April 2006 thread on this list about the TDM400P on a  
net4801, in which Kevin Fleming wrote[8] that "the ringing generators  
on the FXS modules require more
current on the 12V power supply than the PCI spec allows."  This  
sounds plausible, but can someone confirm?

On a related note, I currently (heh heh) have the 1.5A power supply  
for my net5501.  So far it's been sufficient for the experimentation  
I've done.  However, I'm happy to pick up the 2.5A supply if adding  
the TDM400P (+ modules) and a 2.5" hard drive will require me to do so.

FWIW, I'm confused about the power requirements after having done  
some homework and come up with this:  The Digium web site says that  
the TDM400P is a PCI 2.2 card[4].   The Soekris web site says that  
the PCI slot on the net5501 is 3.3v only.   I'm not clear after  
skimming Wikipedia article[9] on PCI as to whether PCI 2.2 is 3.3v- 
only or if it's just that 3.3v is a commonly used implementation.    
Obviously, I'm not an expert in such things.

Any advice/feedback would be appreciated.

thanks,

Graham Freeman
General Manager, Cernio Technology Cooperative
Email/Jabber:  graham.freeman at cernio.com
+1 415 462 2991 home office (0900 to 2100 San Francisco time)
www.cernio.com


[1] m0n0wall - http://m0n0.ch/wall/
[2] FXS = the port you'd plug an analog phone into.  FXO = the port  
you'd use to connect to an analog telco line.
[3] AskoziaPBX - http://askozia.com/pbx
[4] TDM400P - http://www.digium.com/en/wheretobuy/digiumdirect/ 
productview.php?product_code=1TDM22BRF-02
[5] S110M FXS module - http://www.digium.com/en/wheretobuy/ 
digiumdirect/productview.php?product_code=1S110MF-01
[6] X100M FXO module - http://www.digium.com/en/wheretobuy/ 
digiumdirect/productview.php?product_code=1X100MF-01
[7] PWR2400B power supply - http://www.digium.com/en/wheretobuy/ 
digiumdirect/productview.php?product_code=1PWR2401BLF-01
[8] Thread on TDM400P with net4801 - http://lists.soekris.com/ 
pipermail/soekris-tech/2006-April/010231.html
[9] Wikipedia article on PCI - http://en.wikipedia.org/wiki/ 
Peripheral_Component_Interconnect