Set frequency to ref when checking 4 d/tone
| Func AX |
23h |
| Param DX |
The dialtone frequency to
check for (14 default) |
| Return AX |
None |
| Delay |
None |
Set the frequency to reference when checking for dialtone
with DIAL_TONE_CHK. This frequency can be determined by running
the program DT_SETUP.EXE. It is NOT necessary to set this
function unless DIAL_TONE_CHK does not detect a dialtone.
If this function is not set then the default value is 14.
14 represents an average frequency returned by a 32ms zero
cross count. Dialtone is actually a dual tone of 350 Hz
and 440 Hz. |