Measurement Specialties USB-1616HS-2 Example Timer outputs, Timer output frequency examples

USB-1616HS-2 User's Guide Functional Details

Each signal (A, B) can be connected as a single-ended connection with respect to the common digital ground (GND). Both encoders need power from an external power source (typically +5 VDC).

Connect each encoder's power input to the external power source. Connect the return to digital common (GND) on the same source.

Ground (to Digital Common1)	To external power
Counter 0 (CNT0) – To Encoder #1 “A”	To ground	2
Counter 1 (CNT1) – To Encoder #1 “B”

Counter 2 (CNT2) – To Encoder #2 “A”

Counter 3 (CNT3) – To Encoder #2 “B”

1The ground depicted at the left is associated with Digital Common on the USB-1616HS-4.

2The ground depicted at the right is associated with the external power source.

Figure 22. Connections from two encoders to screw terminals on the USB-1616HS-2

Timer outputs

Two 16-bit timer outputs are built into every USB-1616HS-2. Each timer output can generate a different square wave with a programmable frequency in the range of 16 Hz to 1 MHz.

Figure 23. Typical USB-1616HS-2 timer channel

Example: Timer outputs

Timer outputs are programmable square waves. The period of the square wave can be as short as 1 µs or as long as 65535 µs. Refer to the table below for examples of timer output frequencies.

		Timer output frequency examples
Divisor	Timer output frequency
1	1 MHz
100	10 kHz
1000	1 kHz
10000	100 Hz
65535	ƒ	15.259 Hz (in asynchronous write)
	ƒ	Turns timer off (for setpoint operation).

The two timer outputs can generate different square waves. The timer outputs can be updated asynchronously at any time.

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