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I have a number of Linksys/Sipura ATAs; SPA-2000, SPA-2002, SPA-3102, etc.  They all seem to behave the same way with regard to providing CPC on their FXS ports --they seem to provide it on received calls, but not on placed calls.  I'd like my station equipment to receive CPC regardless of whether the call was placed or received.  Is it possible to do this?

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I don't believe you can use CPC in both directions without it "disabling" the CPC feature.  Here's an exert from the ATA Administration Guide that covers the CPC Delay option.  It talks about the downfall of changing the polarity reversal feature:

"Delay in seconds after caller hangs up when the Linksys IP phone starts removing the tip-and-ring voltage to the attached equipment of the called party. Range: 

0–255 seconds.

Linksys IP phone has had polarity reversal feature since release 1.0 which can be applied to both the caller and the callee end. This feature is generally used for

answer supervision on the caller side to signal to the attached equipment when the call has been connected (remote end has answered) or disconnected (remote

end has hung up). This feature should be disabled for the called party (in other words, by using the same polarity for connected and idle state) and the CPC

feature should be used instead.

Without CPC enabled, reorder tone will is played after a configurable delay.

If CPC is enabled, dial tone will be played when tip-to-ring voltage is restored Resolution is 1 second.

The default is 2."

Hope that helps.

This seems to have been topical on several forums.

I have the same problem and would also like my station equipment to receive CPC on outgoing calls.  I use both the PAP2T & 3102 devices.

I have read the ATA Administration Guide.  Although polarity reversal can be used for answer supervision, it does not address the scenario of outgoing calls that are rejected.  Here, the call state becomes “invalid”, and after the “off hook warning” tone plays the line hangs “off hook” indefinitely.  As neither CPC nor polarity reversal can be used to detect the “invalid” call state, tone detection is the only option - far less reliable and not supported with all equipment.

The ability to provide CPC on outgoing calls would appear simple to implement.  Does Linksys envisage the possibility of CPC on outgoing calls in future firmware releases?

In my case I need it for a door phone.  It's a Bogen ADP1, which only has a single button.  The button takes it off-hook.  I have the analog phone line it's connected to configured as a PLAR.  The ADP1 recognizes CPC.  The Linksys/Cisco ATAs, despite having a dizzying array of options don't seem to have one to enable CPC on outbound calls.  I agree, it should be trivial to implement.


Did you ever figure out CPC for outbound calls?

I just found that Obi ( the original makers of the SPA) supports it - I would love if we can get this on any of the current spa's.


No I didn't.  We have door phones connected to PAP2T & 3102 devices and have had to generate a DTMF "D" on the door phones to instigate call termination.

I would be interested to hear if a solution is available though.


Sorry Cisco - I tried for hours to get a PAP2T, SPA2102, SPA112, and SPA122 to  work but with no luck,

I went out and ordered the OBI100 (the original manufacturer of the SPA's) and with in 5 minutes the Bogen was working.

By default they have CPC enabled BOTH for incoming and outgoing. (obviously you can disable it for either incoming or outgoing and for both if that's what you need BUT they give you the options) I did tweak the delay to 1 and time to .5 just so its quicker.

Cisco maybe you guys can take this into consideration that ATA's really do need CPC on outbound.

I am fighting now with a SPA8000 connected to a analog PABX with similar issue, and CPC would really help out.

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