The following tables lists the default input terminals for various counter measurements. You can use a different PFI line for any of the input terminals. To change the PFI input for a measurement, use the NIDAQmx channel attributes/properties.
For information about counters on CompactRIO SingleBoard controllers, refer to the Counter input and Output section in CompactRIO SingleBoard Controller Physical Channels.
NI 9401, NI 9421, NI 9422, NI 9423, NI 9436, and NI 9437 (8Channel)
Measurement 
Ctr0 
Ctr1 
Ctr2 
Ctr3 
Count Edges 
 Edges: PFI 0
 Count Direction: PFI 2

 Edges: PFI 4
 Count Direction: PFI 6

 Edges: PFI 3
 Count Direction: PFI 0

 Edges: PFI 7
 Count Direction: PFI 4

Pulse Width Measurement 
PFI 1 
PFI 5 
PFI 2 
PFI 6 
Period/Frequency Measurement (Low Frequency with One Counter) 
PFI 1 
PFI 5 
PFI 2 
PFI 6 
Period/Frequency Measurement (High Frequency with Two Counters) 
PFI 0 
PFI 4 
PFI 3 
PFI 7 
Period/Frequency Measurement (Large Range with Two Counters) 
PFI 0 
PFI 4 
PFI 3 
PFI 7 
Semiperiod Measurement 
PFI 1 
PFI 5 
PFI 2 
PFI 6 
TwoEdge Separation Measurement 




Position Measurement 
 A: PFI 0
 B: PFI 2
 Z: PFI 1

 A: PFI 4
 B: PFI 6
 Z: PFI 5

 A: PFI 3
 B: PFI 0
 Z: PFI 2

 A: PFI 7
 B: PFI 4
 Z: PFI 6

NI 9402 and NI 9435 (4Channel)
Measurement 
Ctr0 
Ctr1 
Ctr2 
Ctr3 
Count Edges 
 Edges: PFI 0
 Count Direction: PFI 2

 Edges: PFI 3
 Count Direction: PFI 1

 Edges: PFI 1
 Count Direction: PFI 0

 Edges: PFI 2
 Count Direction: PFI 3

Pulse Width Measurement 
PFI 1 
PFI 2 
PFI 3 
PFI 0 
Period/Frequency Measurement (Low Frequency with One Counter) 
PFI 1 
PFI 2 
PFI 3 
PFI 0 
Period/Frequency Measurement (High Frequency with Two Counters) 
PFI 0 
PFI 3 
PFI 1 
PFI 2 
Period/Frequency Measurement (Large Range with Two Counters) 
PFI 0 
PFI 3 
PFI 1 
PFI 2 
Semiperiod Measurement 
PFI 1 
PFI 2 
PFI 3 
PFI 0 
TwoEdge Separation Measurement 




Position Measurement 
 A: PFI 0
 B: PFI 2
 Z: PFI 1

 A: PFI 3
 B: PFI 1
 Z: PFI 2

 A: PFI 1
 B: PFI 0
 Z: PFI 3

 A: PFI 2
 B: PFI 3
 Z: PFI 0

NI 9411 (6Channel)
Measurement 
Ctr0 
Ctr1 
Ctr2 
Ctr3 
Count Edges 
 Edges: PFI 0
 Count Direction: PFI 2

 Edges: PFI 3
 Count Direction: PFI 5

 Edges: PFI 2
 Count Direction: PFI 1

 Edges: PFI 5
 Count Direction: PFI 4

Pulse Width Measurement 
PFI 1 
PFI 4 
PFI 0 
PFI 3 
Period/Frequency Measurement (Low Frequency with One Counter) 
PFI 1 
PFI 4 
PFI 0 
PFI 3 
Period/Frequency Measurement (High Frequency with Two Counters) 
PFI 0 
PFI 3 
PFI 2 
PFI 5 
Period/Frequency Measurement (Large Range with Two Counters) 
PFI 0 
PFI 3 
PFI 2 
PFI 5 
Semiperiod Measurement 
PFI 1 
PFI 4 
PFI 0 
PFI 3 
TwoEdge Separation Measurement 




Position Measurement 
 A: PFI 0
 B: PFI 2
 Z: PFI 1

 A: PFI 3
 B: PFI 5
 Z: PFI 4

 A: PFI 2
 B: PFI 1
 Z: PFI 0

 A: PFI 5
 B: PFI 4
 Z: PFI 3

The following tables list the output terminals for counter output. You can use a different PFI line for any of the output terminals.
NI 9401, NI 9472, NI 9474, NI 9475, and NI 9485 (8Channel)
Ctr0 
Ctr1 
Ctr2 
Ctr3 
FreqOut 
PFI 3 
PFI 7 
PFI 1 
PFI 5 
PFI 2 
NI 9481, NI 9482, and NI 9402 (4Channel)
Ctr0 
Ctr1 
Ctr2 
Ctr3 
FreqOut 
PFI 0 
PFI 3 
PFI 1 
PFI 2 
PFI 1 
NI 9361 (8Counters)
Measurement 
Ctr0 
Ctr1 
Ctr2 
Ctr3 
Ctr4 
Ctr5 
Ctr6 
Ctr7 
Count Edges 
 Edges: PFI 0
 Count Direction: PFI 7
 Reset: PFI4

 Edges: PFI 1
 Count Direction: PFI 6
 Reset: PFI5

 Edges: PFI 2
 Count Direction: PFI 5
 Reset: PFI6

 Edges: PFI 3
 Count Direction: PFI 4
 Reset: PFI7

 Edges: PFI 4
 Count Direction: PFI 3
 Reset: PFI0

 Edges: PFI 5
 Count Direction: PFI 2
 Reset: PFI1

 Edges: PFI 6
 Count Direction: PFI 1
 Reset: PFI2

 Edges: PFI 7
 Count Direction: PFI 0
 Reset: PFI3

Duty Cycle Measurement 
PFI 0 
PFI 1 
PFI 2 
PFI 3 
PFI 4 
PFI 5 
PFI 6 
PFI 7 
Pulse Width Measurement 
PFI 0 
PFI 1 
PFI 2 
PFI 3 
PFI 4 
PFI 5 
PFI 6 
PFI 7 
Period/Frequency Measurement (Dynamic Averaging) 
PFI 0 
PFI 1 
PFI 2 
PFI 3 
PFI 4 
PFI 5 
PFI 6 
PFI 7 
Position Measurement 
 A: PFI 0
 B: PFI 4
 Z: PFI 7

 A: PFI 1
 B: PFI 5
 Z: PFI 6

 A: PFI 2
 B: PFI 6
 Z: PFI 5

 A: PFI 3
 B: PFI 7
 Z: PFI 4

 A: PFI 4
 B: PFI 0
 Z: PFI 3

 A: PFI 5
 B: PFI 1
 Z: PFI 2

 A: PFI 6
 B: PFI 2
 Z: PFI 1

 A: PFI 7
 B: PFI 3
 Z: PFI 0

Velocity 







