Commodore Plus 4 - Page 399

The Modem and Other RS232 Devices 387
Line-by-Line Explanation
10 Remind the user he or she is originating the communication.
20 Receive the number to dial.
30 Check for the correct length of the number.
40 Hang up the phone.
50 Wait.
60 Pick up the phone.
70 Wait.
80 I points to the digits. Get the value of a digit.
90 If not a valid digit, leave.
100 A zero is really 10 pulses.
110 J counts the pulses.
120 Hang up and wait.
130 Pick up and wait. Go on to the next pulse.
140 Wait, then go on to the next digit.
150 Dialing is completed.
160 Print error message.
170 Hang up the phone.
180 Open the RS232 port.
190 Get a byte from the RS232 buffer; if not a null, print it on the screen.
200 Get a byte from the keyboard; if a null, go back to 190.
210 Check for Q key pressed with Q key to quit.
220 Send the character to RS232.
230 Go back to 190.
240 Close the RS232 port and go to 170.
Example: This example waits to answer the phone, and then starts communicating until a
88 Q is typed.
10 PRINTCHR$(147)//MAKE SURE A-0 SWITCH IS ON A":PRINT:
PRINT