Timer Outputs - Measurement Computing PCI-2513 User Manual

PCI-2513 User's Guide
+5 VDC, pin 19
Ground (to Digital Common)
Pin 35, 36, or 40
Counter 0 (CNT0), pin 5 –
To Encoder #1 "A"
Counter 1 (CNT1), pin 39 –
To Encoder #1 "B"
Figure 15. Two encoders connected to pins on the SCSI connector*
* Connections can instead be made to the associated screw-terminals of a connected TB-100 terminal connector
option.
Each signal (A, B) can be connected as a single-ended connection with respect to the common digital ground
(GND). Both encoders can draw their power from the +5 V power output (pin 19) on the 68-pin SCSI
connector.
Connect each encoder's power input to +5 V power. Connect the return to digital common (GND) on the same
connector. Make sure that the current output spec is not violated.
With the encoders connected in this manner, there is no relative positioning information available on encoder #1
or #2 since there is no Z signal connection for either. Therefore only distance traveled and velocity can be
measured for each encoder.

Timer outputs

Two 16-bit timer outputs are built into the PCI-2513. Each timer is capable of generating a different square
wave with a programmable frequency in the range of 16 Hz to 1 MHz.
Counter 2 (CNT2), pin 4 –
To Encoder #2 "A"
Counter 3 (CNT3), pin 38 –
To Encoder #2 "B"
Encoder #1
Figure 16. Typical PCI-2513 timer channel
26
Functional Details
Encoder #2