Not sure the 9375 is the best choice or a rotary encoder. You need something to cause an interrupt at the encoder data rate. I use the 9375 just for control signals out and digital status in.
This is an example of my setup code:
// ------------------------------------------------------------------------------------------------------------------------
// Initialize the Module A2 NI9375 16-Channel DI
// Note: The DIN and DOUT tasks must be started before the Analog task is started, so that the DIN and DOUT tasks are
// known the first time the Analog interrupt happens.
// ------------------------------------------------------------------------------------------------------------------------
// Create the DIN task
DAQmxErrChk( DAQmxCreateTask( "MbDasDigitalIn", &DinTaskHandle ) );
// Create Digital In channel defined as all 32 bits read at once
DAQmxErrChk( DAQmxCreateDIChan( DinTaskHandle, "MbDas-DIO/port0", "DIN", DAQmx_Val_ChanForAllLines ) );
DAQmxErrChk ( DAQmxStartTask( DinTaskHandle ) );
SysLogEntry( "\Initialized Module A6 Digital Input Channels. Started DinTaskHandle Task.\n" );
Sleep( 100 );
// ------------------------------------------------------------------------------------------------------------------------
// ------------------------------------------------------------------------------------------------------------------------
// Initialize the NI9375 16-Channel DO
// ------------------------------------------------------------------------------------------------------------------------
// Create the DOUT task
DAQmxErrChk( DAQmxCreateTask( "MbDasDigitalOut", &DoutTaskHandle ) );
// Create Digital Out channel defined as all 16 bits read at once
DAQmxErrChk( DAQmxCreateDOChan( DoutTaskHandle, "MbDas-DIO/port1", "DOUT", DAQmx_Val_ChanForAllLines ) );
// Start the task
DAQmxErrChk ( DAQmxStartTask( DoutTaskHandle ) );
And then within an interrupt handler, this code:
if ( DinTaskHandle )
{
DAQmxReadDigitalScalarU32 ( DinTaskHandle, 0.0, &dinUInt, 0 );
*( unsigned int * )&Din = dinUInt;
}
That *( unsigned int * )&Din = dinUInt; writes the UINT into a bit structure. One thing to remember is that while you read and write 32 bit integers, you are only interested in the lower 16 bits.
