National Instruments ENET-232 Series, Manual

Page: 97 / 237

Retrieving the Serial Interface Type (RS-232 or
RS-485)
There are two ways to retrieve the serial interface type (RS-232 or RS-
485):
Read the NI-VISA wire mode attribute.
The NI-Serial software uses programmatic control codes and the
DeviceIoControl Windows function to retrieve the serial interface
type.
To retrieve the serial interface type using the DeviceIoControl Windows
function, complete the following steps:
1. Add the following lines to your source code:
#include <winioctl.h>
#include <NiSerial.h>
Note The header file
NiSerial.h
is included on your NI-
Serial software CD. You also can find it in the
NI-Serial
folder where you installed your National Instruments
software (typically,
C:\Program Files\National Instruments\NI-
Serial
).
2. The
SERIAL_INTERFACE
attribute can have the following values:
RS485_INTERFACE
RS232_INTERFACE
3. To retrieve the serial interface type, use
NISERIAL_GET_INTERFACE_TYPE and DeviceIoControl with the
following code:
SERIAL_INTERFACE l_SerialInterface;
DWORD l_ByteCount;
DeviceIoControl (
PortHandle,
NISERIAL_GET_INTERFACE_TYPE,
(LPVOID) NULL,