🚀 go-pugleaf

From article <1eg588INNs78@uniwa.uwa.edu.au>, by markd@uniwa.uwa.edu.au (Mark Diamond):
> gt8741b@prism.gatech.edu (Chris Adams) writes:
> 
>>Can someone tell me what the frequencies of the buttons on a telephone generate
>>and what the dial tone frequency is?  I am trying to build something, and I
>>need to recognize a dial tone, and generate button presses.
>>--
>>Chris Adams                       | "If tin whistles are made of tin,
>>Georgia Tech                      |  what do they make foghorns from?"
>>Internet: gt8741b@prism.gatech.edu|       --  Lonnie Donegan
>>----------------------------------+ 
> 
> I don't recall the tone frequencies.  However, they are easily found in
> the published ISO, British and Australian standards.  Presumably these,
> or the USA equivalent should be easily obtainable.  Basically, each
> digit (as well as the * and # functions) are composed of 2 frequencies
> sounded together.  All keys in the same Column share the same lower tone
> (with the lower tone ascending across columns) ... and similarly for the
> rows.
>
 
Sorry, missed the original message - here they are anyway...

          1     2     3     A  :  697 Hz

          4     5     6     B  :  770 Hz
                                           (low tones)
          7     8     9     C  :  852 Hz

          *     0     #     D  :  941 Hz
        ----  ----  ----  ----
        1209  1336  1477  1633 Hz
               (high tones)

//Paul

-- 
| Paul Russell              | "Some instructions have legal operation codes |
| Experimental Psychology   |  but try to perform nonsensical operations.   |
| Sussex University, Falmer |  These are called insane instructions."       |
| Brighton BN1 9QG, England |             -- Motorola DSP 56k User's Manual |