simultaneous analog and counter input with occasional digital output on USB-1808X

[PhilipW]

Using 3 analog inputs and 1 counter I am able to receive voltage and encoder data simultaneously using DaqInScan() on a USB-1808X. The scan options include MacDaq.ScanOptions.Background and MccDaq.ScanOptions.Continuous.

 

Now I want to include occasional digital output. Within an application a user will click a button and the following code will be executed:

 

ushort DataValue = 255;

PortOutputNum = MccDaq.DigitalPortType.AuxPort;

MccDaq.ErrorInfo ULStat = daqBoard.DOut(PortOutputNum, DataValue);

 

The universal library returns the error:

 

Digital port not configured correctly for requested operation.

 

What I’m I doing wrong?

[DAQman]

The four-bit port is an input by default. Use DConfigPort to make it an output, and it's best to do this at the beginning of the program. Or you could configure each bit individually using DConfigBit.

 

[PhilipW]

So the I/O port has four-bits (0 - 3) Do these bits correspond the screw terminals labelled DIO0, DIO1, DIO2 and DIO3?

[DAQman]

[PhilipW]

In an earlier post, you suggested I use DConfigPort() or DConfigBit().

If I use DConfigBit(AuxPort, 0, DigitalOut) I have to wire screw terminal DIO0 since bitNum=0.

If I use DConfigPort(AuxPort, DigitalOut) which bitNum is being used? Which screw terminal do I wire?

[DAQman]

DConfigPort sets all four bits to be output. DConfigBit is just one bit. So you could do:

 DConfigBit(AuxPort, 0, DigitalOut)

 DConfigBit(AuxPort, 1, DigitalOut)

 DConfigBit(AuxPort, 2, DigitalOut)

 DConfigBit(AuxPort, 3, DigitalOut)

or just

DConfigPort(AuxPort, DigitalOut)