This documentation is archived and is not being maintained.


The DCB entry locks the modem's port speed to a specific default. It also controls XON/XOFF software flow-control settings.


The ProCalc tool, which is included in the Microsoft Windows Driver Kit (WDK), should be used to create this entry. For more information about ProCalc, see Using ProCalc. For more information about using ProCalc to create this entry, see Locking the Port Speed (DCB).



A data structure that contains DWORD and WORD hexadecimal values.


The following example of a <b>DCB</b> entry is taken from the sample INF file, <i>MdmHayes.inf</i>:

HKR,, DCB, 1, 1C,00,00,00, 80,25,00,00, 15,20,00,00, 00,00, 0a,00, 0a,00, 08, 00, 00, 11, 13, 00, 00, 00


Typically, the only member that is modified is the baud rate. The other members are used in advanced applications, which are beyond scope of this document.



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