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How FastLink II Operates the Modem
FastLink II operates a modem based on the command string and result string settings for that modem:
A command string is a string sent to the modem to cause it to perform an operation, such as to reset
itself, dial a number, or wait for a call.
A result string is a string sent back from the modem to indicate the result of an operation.
When FastLink II initiates a call to a server, it first sends three command strings in succession: Reset, Init, and
Additional. It then sends the Dial string, followed by the phone number.
The Auto-answer string is only used for dialback. After making the initial connection, FastLink II hangs up,
sends the Reset, Init, and Additional strings, then sends the Auto-answer string to await the return phone call
from the server.
Command Strings
The modem command strings should perform functions as follows:
The Reset string resets the modem to the factory defaults.
The Init string should:
−−
Configure error-correction and compression
−−
Enable hardware flow control
−−
Enable CD (Carrier Detect) high on connection
−−
Enable hang-up on DTR (Data Terminal Ready) low.
−−
Set the CONNECT report string to the modem’s DCE speed. This will show the true
speed of the connection.
The Additional string contains any additional initialization you’d like.
The Dial string contains the dial prefix sent before the phone number.
The Auto-answer string should put the modem in auto-answer mode.
