Commodore modem 300 User Manual page 74

2) Program the telephone to be off hook.
3) Wait 2 seconds (for i = 1 to 500:next:rem 2 second delay)
4) Dial each digit and follow it with a delay (for i = 1 to 50:next)
5) When a carrier(high pitched tone) is detected, the Modem/300
automatically goes on-line with the computer you are connecting
with.
6) Program the phone to hang up when you are finished.
Here is the procedure to answer a call:
1) Set the answer/originate switch to "A" for answer.
2) To manually answer, program the telephone to be OFF the hook.
3) To automatically answer, detect if the phone is ringing then pro­
gram the phone to be OFF the hook.
4) The Modem/300 automatically answers the call.
5) Program the phone to hang up when you are finished.
DETECTING CARRIER
Your Commodore Modem/300 has been shipped from the factory
with the ability to detect carrier on the Commodore 128,64, SX-64 or
VIC 20 computers.
This ability is useful in an unattended auto-answer mode. By moni­
toring the carrier detect line, the computer can be programmed to
hang up after loss of carrier. This may not be foolproof however,
since a caller may forget to hang up. You may want to monitor the
transmit and receive data lines, and if there is no activity for five
minutes or so, the program should have the modem hang up.
To detect carrier on the Commodore 128,64, or SX-64, the following
statements can be used in a BASIC program:
OH = 56577:
IF ((PEEK(OH) AND 16) = 16)THEN PRINT " NO CARRIER" :
IF ((PEEK(OH) AND 16) = 0) THEN PRINT " CARRIER DETECTED"
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