ASYNC GETBAUDRATE: Difference between revisions
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{{DISPLAYTITLE:ASYNC_GETBAUDRATE}} | |||
This function returns the bit rate. | This function returns the bit rate. | ||
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;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. | ;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. | ||
[[Category:IOCtl | [[Category:IOCtl Function]] | ||
Latest revision as of 18:49, 22 October 2021
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.