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This page contains all of the posts and discussion on MemeStreams referencing the following web page: AMIS: DTMF Data Link (kind of) [ZIP]. You can find discussions on MemeStreams as you surf the web, even if you aren't a MemeStreams member, using the Threads Bookmarklet.

AMIS: DTMF Data Link (kind of) [ZIP]
by k at 11:02 am EDT, Jun 15, 2005

While I don't really care about forwarding voice mail, the use of DTMF tones to create a reliable datalink layer is something I was trying to do. A pair of FSR radios, some DTMF chips and some PICs and I have a reliable, low speed (~45bps) data communcations with around a mile range for under $50. This is far more flexible then the model airplane remote controls that cost over $75.

Cisco has some info on it too.

[ This wouldn't have anything to do with advanced remote package delivery systems, would it? -k]

Package System rumors are completely false!
by Acidus at 12:19 pm EDT, Jun 15, 2005

[ This wouldn't have anything to do with advanced remote package delivery systems, would it? -k]

News Flash:
Most Significant Bit Labs retracts its statement yesterday regarding its interest in remote package delivery systems. This was made in junior officer who didn't fully understand the situation. The actual project is the development of high altitude weather balloons. We at MSB Labs understand how these 2 systems look very similar, and how this error was made.

Allow us to state categorically that MSB Labs has no interest in package delivery systems, especially advanced or remotely controlled package delivery systems.

Thank you for your time

AMIS: DTMF Data Link (kind of) [ZIP]
by Acidus at 3:56 pm EDT, Jun 14, 2005

The AMIS protocol was designed in the late 80s early 90s to allow Voice mail systems of different vendors to automatically transmit voice mail messages to each other.

It uses DTMF tones to communicate back and forth, establishing who the voice message is for, where it is coming from, and for the destination system to specify if the mailbox is full, to provide a forwarding number, etc. The use of timeouts, checksums and acknowledgements make this a reliable protocol, with a variable payload length. The analog voice message itself is not digitized, and is played real time. A sample session looks like:

-A dials B
-Using DTMF tones, A and B agree on a protocol.
-A tells B for the message is for, who it is from
-B confirms information is correct and mailbox is available
-A plays voice message "Hi Billy, this is Jill..."
-A signals message is over
-System gracefully terminate.

Cisco has some info on it too.

AMIS: DTMF Data Link (kind of) [ZIP]
by Rattle at 5:25 pm EDT, Jun 14, 2005

Acidus cranks out another neat hack.

The AMIS protocol was designed in the late 80s early 90s to allow Voice mail systems of different vendors to automatically transmit voice mail messages to each other.
It uses DTMF tones to communicate back and forth, establishing who the voice message is for, where it is coming from, and for the destination system to specify if the mailbox is full, to provide a forwarding number, etc. The use of timeouts, checksums and acknowledgements make this a reliable protocol, with a variable payload length. The analog voice message itself is not digitized, and is played real time. A sample session looks like:
-A dials B
-Using DTMF tones, A and B agree on a protocol.
-A tells B for the message is for, who it is from
-B confirms information is correct and mailbox is available
-A plays voice message "Hi Billy, this is Jill..."
-A signals message is over
-System gracefully terminate.
While I don't really care about forwarding voice mail, the use of DTMF tones to create a reliable datalink layer is something I was trying to do. A pair of FSR radios, some DTMF chips and some PICs and I have a reliable, low speed (~45bps) data communcations with around a mile range for under $50. This is far more flexible then the model airplane remote controls that cost over $75.
Cisco has some info on it too.