Asterisk AMI and DTMF

Asterisk Asterisk Support
1

I have an application where I am using AMI originate to start a call.

This bridges a call between an extension (1001) and my dialplan which waits for DTMF tones from the extension. If the user presses 8, then the dialplan should play another file, if the user presses 8 again it plays another file and so on and so on.

This works fine when digit 8 is presses from a SIP phone, but when trying to use the AMI action: playDTMF it doesn’t work.

the tone is hear from the phone and I can see the activity in the asterisk CLI.
To be able to see it in the asterisk logs I first have to create a local channel to send the DTMF too.
While its being displayed in the asterisk CLI it doesn’t step over to play the next file.

Here is an example of my asterisk CLI with key presses being made from a phone:
[2015-07-15 11:30:59.831] DTMF[14264][C-00000019]: channel.c:3945 __ast_read: DTMF end ‘8’ received on SIP/1001-00000018, duration 180 ms
[2015-07-15 11:30:59.832] DTMF[14264][C-00000019]: channel.c:3986 __ast_read: DTMF end accepted with begin ‘8’ on SIP/1001-00000018
[2015-07-15 11:30:59.832] DTMF[14264][C-00000019]: channel.c:4015 __ast_read: DTMF end passthrough ‘8’ on SIP/1001-00000018
[2015-07-15 11:30:59.832] DTMF[14267][C-00000019]: channel.c:3945 __ast_read: DTMF end ‘8’ received on Local/112@extensions-00000009;2, duration 180 ms
[2015-07-15 11:30:59.832] DTMF[14267][C-00000019]: channel.c:4015 __ast_read: DTMF end passthrough ‘8’ on Local/112@extensions-00000009;2
– Executing [112@extensions:80] NoOp(“Local/112@extensions-00000009;2”, “USERSTOPPED”) in new stack
– Executing [112@extensions:81] NoOp(“Local/112@extensions-00000009;2”, “60”) in new stack
– Executing [112@extensions:82] NoOp(“Local/112@extensions-00000009;2”, “8”) in new stack
– Executing [112@extensions:83] Set(“Local/112@extensions-00000009;2”, “VAR=USERSTOPPED”) in new stack
– Executing [112@extensions:84] Set(“Local/112@extensions-00000009;2”, “FRE=9”) in new stack
– Executing [112@extensions:85] GotoIf(“Local/112@extensions-00000009;2”, “1?heard1:notheard9”) in new stack
– Goto (extensions,112,130)

Compared to the same activity when the DTMF tone is generated by AMI:

[2015-07-15 11:30:59.693] DTMF[14264][C-00000019]: channel.c:4031 __ast_read: DTMF begin ‘8’ received on SIP/1001-00000018
[2015-07-15 11:30:59.693] DTMF[14264][C-00000019]: channel.c:4042 __ast_read: DTMF begin passthrough ‘8’ on SIP/1001-00000018
[2015-07-15 11:30:59.693] DTMF[14267][C-00000019]: channel.c:4031 __ast_read: DTMF begin ‘8’ received on Local/112@extensions-00000009;2
[2015-07-15 11:30:59.693] DTMF[14267][C-00000019]: channel.c:4035 __ast_read: DTMF begin ignored ‘8’ on Local/112@extensions-00000009;2
– Executing [112@extensions:71] NoOp(“Local/112@extensions-00000009;2”, “SUCCESS”) in new stack
– Executing [112@extensions:72] NoOp(“Local/112@extensions-00000009;2”, “-1”) in new stack
– Executing [112@extensions:73] NoOp(“Local/112@extensions-00000009;2”, “”) in new stack
– Executing [112@extensions:74] Set(“Local/112@extensions-00000009;2”, “VAR=SUCCESS”) in new stack
– Executing [112@extensions:75] Set(“Local/112@extensions-00000009;2”, “FRE=8”) in new stack
– Executing [112@extensions:76] GotoIf(“Local/112@extensions-00000009;2”, “0?heard1:notheard8”) in new stack
– Goto (extensions,112,77)

This is my a snipet of my dialplan:
same =>n,NoOp(Play audioFile)
same =>n,ControlPlayback(dir/filename,4000,*,#,8,0)
same =>n,NoOp(${CPLAYBACKSTATUS})
same =>n,NoOp(${CPLAYBACKOFFSET})
same =>n,NoOP(${CPLAYBACKSTOPKEY})
same =>n,SET(VAR=${CPLAYBACKSTATUS})
same =>n,SET(FRE=1)
same =>n,GotoIf($["${VAR}" = “USERSTOPPED”]?heard1:notheard1)

My AMI command is:
action:playDTMF
channel:Local/112@extensions-00000009;2
digit:8

I’m assuming the DTMF is going to the wrong leg of the call and asterisk isn’t passing it to ControlPlayback for recognition.

Could anyone advise how I might be able to get same =>n,ControlPlayback(dir/filename,4000,*,#,8,0) to recognise the DTMF tone sent via AMI?

2

DTMF sent from AMI will go out on the channel you specify, not be seen as incoming. If there is no alternative to using DTMF, you must interpose a Local channel and send the DTMF on the ;1 side of that.

If you do it properly, the caller won’t hear the tones.

3

Hi,

I’ve read a couple of posts and I’ve tried to interpose a local channel, although maybe incorrectly.

My first attempt was to the send the DTMF tones to the SIP channel:

AMI code:

action:playDTMF
channel:SIP/1001-00000014
digit:8

based on seeing this cannel in my asterisk CLI

– Executing [112@from-internal:7] ControlPlayback(“SIP/1001-00000014”, “audiofile,4000,*,#,8,0”) in new stack
– <SIP/1001-00000014> Playing audiofile.slin’ (language ‘en’)
– Executing [112@from-internal:8] NoOp(“SIP/1001-00000014”, “SUCCESS”) in new stack
– Executing [112@from-internal:9] NoOp(“SIP/1001-00000014”, “-1”) in new stack
– Executing [112@from-internal:10] NoOp(“SIP/1001-00000014”, “”) in new stack
– Executing [112@from-internal:11] Set(“SIP/1001-00000014”, “VAR=SUCCESS”) in new stack
– Executing [112@from-internal:12] Set(“SIP/1001-00000014”, “FRE=1”) in new stack
– Executing [112@from-internal:13] GotoIf(“SIP/1001-00000014”, “0?heard1:notheard1”) in new stack

As this failed I tried adding in a local channel and sending the DTMF tones to that channel:

AMI:
action:playDTMF
channel:Local/112@from-internal-0000000e;2
digit:8

based on seeing this in my asterisk CLI:
– Executing [113@from-internal:1] NoOp(“SIP/1001-00000015”, “”) in new stack
– Executing [113@from-internal:2] Dial(“SIP/1001-00000015”, “Local/112@from-internal”) in new stack
– Called Local/112@from-internal
– Executing [112@from-internal:1] NoOp(“Local/112@from-internal-0000000e;2”, “”) in new stack
– Executing [112@from-internal:2] Answer(“Local/112@from-internal-0000000e;2”, “”) in new stack
– Local/112@from-internal-0000000e;1 answered SIP/1001-00000015
– Channel SIP/1001-00000015 joined ‘simple_bridge’ basic-bridge
– Channel Local/112@from-internal-0000000e;1 joined ‘simple_bridge’ basic-bridge
> 0x7f63b8007e10 – Probation passed - setting RTP source address to 192.168.200.34:63300
– Executing [112@from-internal:3] NoOp(“Local/112@from-internal-0000000e;2”, “Local/112@from-internal-0000000e;2”) in new stack

-- Executing [112@from-internal:5] BackGround("Local/112@from-internal-0000000e;2", "welcome-message") in new stack
-- <Local/112@from-internal-0000000e;2> Playing 'audiofile.slin' (language 'en')
-- Executing [112@from-internal:6] NoOp("Local/112@from-internal-0000000e;2", "Play 500Hz_-80dBFS") in new stack
-- Executing [112@from-internal:7] ControlPlayback("Local/112@from-internal-0000000e;2", "audiofile,4000,*,#,8,0") in new stack
-- <Local/112@from-internal-0000000e;2> Playing 'audiofile.slin' (language 'en')
-- Executing [112@from-internal:8] NoOp("Local/112@from-internal-0000000e;2", "SUCCESS") in new stack
-- Executing [112@from-internal:9] NoOp("Local/112@from-internal-0000000e;2", "-1") in new stack
-- Executing [112@from-internal:10] NoOp("Local/112@from-internal-0000000e;2", "") in new stack
-- Executing [112@from-internal:11] Set("Local/112@from-internal-0000000e;2", "VAR=SUCCESS") in new stack
-- Executing [112@from-internal:12] Set("Local/112@from-internal-0000000e;2", "FRE=1") in new stack
-- Executing [112@from-internal:13] GotoIf("Local/112@from-internal-0000000e;2", "0?heard1:notheard1") in new stack

So I believe i’m sending it to the correct channel, but the tones not being recognised by ControlPlayback which is expecting a keypress of 8.

4

I said send it to the ;1 side. You have sent it to the ;2 side. You must send it to a channel that is NOT running dialplan. If you send it to one running dialplan, the DMTF will go away from the dialplan, not towards it.

A local channel is a pair of channels that forward media between each other. The one that is nearer the caller ends in ;1 and the one that normally runs the dialplan ends in ;2. The rest of the name is the same.

5

Excellent, that’s now working.

I was aware (sort of) of sending it (or trying to) to the 1 side of the channel but I didn’t quite know the meaning of the ;1 and ;2 for the pairs of the local channel and therefore how to do it.

Your explaining made it blindingly obvious, or maybe I was staring at it for too long.

Thanks very much.