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ASYNC GETBAUDRATE: Difference between revisions

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Created page with "This function returns the bit rate. ; Category: IOCTL_ASYNC (01h) ; Function: ASYNC_GETBAUDRATE (61h) ==Parameter Packet Format== None. Packet pointer must be NULL. ==Da..."
 
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;Bit Rate
:A binary integer representing the actual bit rate of the COM device in bits-per-second, rounded to the nearest whole number.


==Returns==
==Returns==

Revision as of 04:17, 24 April 2020

This function returns the bit rate.

Category
IOCTL_ASYNC (01h)
Function
ASYNC_GETBAUDRATE (61h)

Parameter Packet Format

None. Packet pointer must be NULL.

Data Packet Format

┌────────────────────────────────────┐
│Field        Length     C Datatype  │
├────────────────────────────────────┤
│Bit Rate     WORD       USHORT      │
└────────────────────────────────────┘
Bit Rate
A binary integer representing the actual bit rate of the COM device in bits-per-second, rounded to the nearest whole number.

Returns

If the call is made with an invalid Parameter Packet value, a general failure error is reported and valid information is not returned in the Data Packet.

Remarks

If a general failure error is not returned, the physical device driver returns the current bit rate of the COM device.

Note
If this function is called when the current bit rate setting of a COM port is greater than what can be stored in a 1-WORD field, the device driver sets the bit rate to 1200 bps (default value) and returns 1200 bps to the user.