INF File Entries for Fax Modems

Fax modems require configuration parameters that are modem specific. For example, the following parameters: hardware flow control; the host-to-modem transmission rate that includes reliable transfers above 19200 bps; and the adaptive answer algorithm. INF file entries are used to configure these parameters.

For incoming data calls, configure the fax-modem to use hardware flow control and a DTE-DCE speed of at least 57600 bps to achieve the best RAS performance. You should also set up the fax-modem with the appropriate RAS settings for the proper modulation, data compression, and error control. Use the AdaptiveAnswer fax entries to configure adaptive answer support.

The fax settings are organized in a hierarchy of registry keys that represent the modem state. The modem class (Class1, Class2)and the current modem operation (Send, Receive, AdaptiveAnswer) define a fax modem state. These registry keys can be configured using INF file entries. Fax INF entries with the same name are allowed at different locations of the fax registry hierarchy.

For a detailed description of the fax INF entries, see Fax Modem INF File Entries. A sample representation of the fax registry key hierarchy follows:

Fax
    ExitCommand
    PreAnswerCommand
    PreDialCommand
    ResetCommand
    SetupCommand
    EnableV17Recv
    EnableV17Send
    FixModemClass
    FixSerialSpeed
    HighestSendSpeed
    LowestSendSpeed
    HardwareFlowControl
    SerialSpeedInit

    Class1
        SetupCommand
        HardwareFlowControl

        Send
            ResetCommand
            SetupCommand
        Receive
            SerialSpeedInit
        AdaptiveAnswer
            AnswerCommand 1
            AnswerCommand 2
            AnswerCommand 3
            ModemResponseFaxDetect
            ModemResponseDataDetect
            SerialSpeedFaxDetect
            SerialSpeedDataDetect
            HostCommandFaxDetect
            HostCommandDataDetect
            ModemResponseFaxConnect
            ModemResponseDataConnect

The Microsoft T.30 protocol engine (T.30) accesses the registry value at the hierarchy location that corresponds to the current fax modem state. If these entries are not defined at a given location of the hierarchy, T.30 searches upward in the hierarchy until it reaches the Fax root. If the entry is not defined at any level in the hierarchy, T.30 tries to auto-detect the value or use the default value.

For example, if a fax-modem receives an adaptive answer in class1, T.30 uses the SetupCommand contained in one of the following registry paths:

1. Fax\Class1\AdaptiveAnswer\SetupCommand

2. Fax\Class1\SetupCommand

3. Fax\SetupCommand

Using the preceding example, if SetupCommand is not defined at any level, T.30 will auto-define SetupCommand using the algorithm described in Modem INF File Entries.

Examples of fax INF file entries to set registry values for two modems follow:

Example 1: USR Courier V.Everything

HKR, Fax, HardwareFlowControl,, "1"
HKR, Fax, SerialSpeedInit,, "57600"
HKR, Fax, ResetCommand,, "AT&FS0=0E0V1Q0"
HKR, Fax, SetupCommand,, "ATS7=255X4&D2&C1&H1&R2&I0"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 1,, "ATE0Q0V1"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 2,, "AT+FCLASS=1"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 3,, "ATE0Q0V1"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 4,, "AT&B1&C1&D2E0Q0V1&A3S0=0"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 5,, "ATS7=60S19=0M1&M4&K1&H1&R2&I0B0X4"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 6,, "AT+FAA=1"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 7,, "ATA"
HKR, Fax\Class1\AdaptiveAnswer, ModemResponseFaxDetect,, "FAX"
HKR, Fax\Class1\AdaptiveAnswer, ModemResponseFaxConnect,, "CONNECT"
HKR, Fax\Class1\AdaptiveAnswer, ModemResponseDataDetect,, "DATA"
HKR, Fax\Class1\AdaptiveAnswer, HostCommandDataDetect,, "ATO"
HKR, Fax\Class1\AdaptiveAnswer, ModemResponseDataConnect,, "CONNECT"

Example 2: Diamond Supra Voice modem

HKR, Fax, HardwareFlowControl,, "1"
HKR, Fax, SerialSpeedInit,, "19200"
HKR, Fax, ResetCommand,, "AT E0 V1 Q0"
HKR, Fax, SetupCommand,, "AT &F2 E0 V1 Q0 X4 &K3"
HKR, Fax, FixModemClass,, "2"
HKR, Fax\Class2, Cl2IsEx,, "1"
HKR, Fax\Class1\AdaptiveAnswer, ModemResponseFaxDetect,, "FAX"
HKR, Fax\Class1\AdaptiveAnswer, ModemResponseDataDetect,, "CARRIER"
HKR, Fax\Class1\AdaptiveAnswer, ModemResponseFaxConnect,, "CONNECT"
HKR, Fax\Class1\AdaptiveAnswer, ModemResponseDataConnect,, "CONNECT"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 1,, "AT &F2 E0 V1 Q0 W1 S95=47 S0=0"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 2,, "ATS7=60 S30=0 L M1 &Q5 \N3 %C3 &K3 B N1 X4"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 3,, "AT+FAE=1"
HKR, Fax\Class1\AdaptiveAnswer\AnswerCommand, 4,, "ATA"

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