NI 653X Device Physical Channels

Digital Input and Output

All NI 653X devices have 32 individually configurable lines of digital input and output that are grouped into four 8-bit ports.

Port	NI-DAQmx Physical Channel Name (Lines)	NI-DAQmx Physical Channel Name (Ports)1
Port 0	Dev1/port0/line0 — Dev1/port0/line7	Dev1/port0
Port 1	Dev1/port1/line0 — Dev1/port1/line7	Dev1/port1
Port 2	Dev1/port2/line0 — Dev1/port2/line7	Dev1/port2
Port 3	Dev1/port3/line0 — Dev1/port3/line7	Dev1/port3
1This physical channel name refers to all eight lines in a port at once.

For Ports 0 through 3, you can configure a port width of eight, 16, or 32 bits. To configure a 32-bit port, use the physical channel name Dev1/port0_32. To configure a 16-bit port, use channel names that refer to all the lines in multiple consecutive ports: Dev1/portP_N, where P is the port number of the lowest numbered port, and N is the total number of lines. For instance, combining Port 2 and 3 into a 16-bit port, you would specify Dev1/port2_16 as the physical channel.

NI 653X devices also have eight fixed-direction lines, grouped into two ports, that use PFI lines. Port 4 is used for input operations; Port 5 is for output.

Port 4 and port 5 can be used as static digital I/O lines or PFI lines. When any of these PFI lines is used as a digital I/O signal, it uses the physical channel name shown in the following table.

PFI Signal	Physical Channel Name
PFI0	Dev1/port4/line0
PFI1	Dev1/port4/line1
PFI2	Dev1/port4/line2
PFI3	Dev1/port4/line3
PFI4	Dev1/port5/line2
PFI5	Dev1/port5/line3
PFI6	Dev1/port5/line0
PFI7	Dev1/port5/line1