ASYNC_GETMODEMINPUT
Returns the modem control input signals.
- Category
- IOCTL_ASYNC (01h)
- Function
- ASYNC_GETMODEMINPUT (67h)
Parameter Packet Format
None. Packet pointer must be NULL.
Data Packet Format
| Field | Length | C Datatype |
|---|---|---|
| Modem Control Input Status | BYTE | UCHAR |
- Modem Control Input Status
- If a bit has a value of 1, the condition is on. If a bit has a value of 0, the condition is off.
- Bit 0-3: Undefined
- Bit 4: Clear To Send (CTS)
- Bit 5: Data Set Ready (DSR)
- Bit 6: Ring Indicator (RI)
- Bit 7: Data Carrier Detect (DCD)
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 modem control input signals of the COM device.