Depending on your X Series device, you can have from eight to 208 analog input channels. An 8-channel X Series device has physical channels ranging from Dev1/ai0 to Dev1/ai7, a 208-channel device from Dev1/ai0 to Dev1/ai207.

Use only the physical channel name of the positive channel (not both) when creating a differential channel.

An X Series device that supports two analog outputs has analog output physical channels named Dev1/ao0 and Dev1/ao1.

An X Series device that supports four analog outputs has analog output physical channels named Dev1/ao0, Dev1/ao1, Dev1/ao2, and Dev1/ao3.

All X Series devices have eight or 32 lines of digital input and output named Dev1/port0/line0 through Dev1/port0/line7 or Dev1/port0/line0 through Dev1/port0/line31. These lines belong to a single port, and the physical channel Dev1/port0 refers to all eight or 32 lines at once. Port 0 can perform both hardware-timed and static digital operations.

X Series devices have two more ports, port 1 and port 2. Port 1 has eight digital I/O lines, Dev1/port1/line0 through Dev1/port1/line7. Port 2 has eight digital I/O lines, Dev1/port2/line0 through Dev1/port2/line7. Port 1 and port 2 can be used as static digital I/O lines or PFI lines, PFI 0..15. When any of PFI lines 0..15 is used as a digital I/O signal, it uses the physical channel name shown in the following table.

Physical channel Dev1/port1 refers to all eight lines, Dev1/port1/line0:7, at once. Physical channel Dev1/port2 refers to all eight lines, Dev1/port2/line0:7, at once.

All X Series devices have four counter/timers referred to by the physical channel names Dev1/ctr0, Dev1/ctr1, Dev1/ctr2, and Dev1/ctr3. Unlike the other I/O types, these physical channel names do not refer to terminals on the I/O connector but instead to circuits within the device. There are five primary signals associated with each counter: SOURCE, GATE, AUX, OUT, and sample clock. NI-DAQmx has default terminals for these signals, except for the sample clock. For counter input tasks, if you know whether your signal provides the SOURCE, AUX, or GATE function and wire your signal to the default, you do not have to set the Input Terminal attribute/property.