Curtis Instruments 1351 User Manual

3 — PROGRAMMABLE PARAMETERS
pg. 49
Return to TOC Curtis Model 1351 – December 2018
High Speed Digital Inputs
ere are two high-speed digital inputs on the 1351. ese inputs can be used to measure input frequency and
pulse width or used as counters/accumulators. ese inputs can also be used for a quadrature (encoder) input,
but they cannot be used as both high-speed inputs and encoders simultaneously. erefore, the function of
each input (pins 14 and 15) must be setup prior to use by setting the following High Speed Digital Input
parameters. See the Encoder 1 parameters, below, for this alternative usage.
INPUTS — HIGH SPEED DIGITAL INPUTS
PARAMETER ALLOWABLE RANGE DEFAULT DESCRIPTION
Count
HS_Input_X_Count
Variable’s CAN Index by Count
Input:
1 = 0x3422 0x00
2 = 0x3425 0x00
0 – 4294967295
0 – 4294967295
Read Only Count is based on the Type parameter selection. The counter
range is 0 – (2
32
) – 1. It will overow and reset to 0.
X = 1 or 2 for the Count: HS_Input_X_Count
-------------------
The counter function has a new VCL feature;
Reset_Pulse_Counter(X)
Description:
Will reset the input counter to 0
Parameter:
X = the input counter to reset: 1 – 2
Pin 14, X = 1
Pin 15, X = 2
Note, this is the same variable in the Monitor menu:
Monitor\Inputs\High Speed Digital Input X\Count
Frequency
HS_Input_X_Frequency
Variable’s CAN Index by
Frequency Input:
1 = 0x3420 0x00
2 = 0x3423 0x00
0 – 50000 Hz
0 – 50000
Read Only Measure the frequency of the incoming signal pulses.
The frequency measurement is derived from the input signal’s
rising to rising edge.
X = 1 or 2 for the Frequency: HS_Input_X_Frequency
Note, this is the same variable in the Monitor menu:
Monitor\Inputs\High Speed Digital Input X\Frequency
Pulse Width
HS_Input_X_Pulse_Wdith
Variable’s CAN Index by Pulse
Width Input:
1 = 0x3421 0x00
2 = 0x3424 0x00
0.0 – 100 %
0 – 1000
Read Only This is the % width of either the high or low pulse, depending on
the Type setting.
X = 1 or 2 for the Frequency: HS_Input_X_Pulse_Width
Note, this is the same variable in the Monitor menu:
Monitor\Inputs\High Speed Digital Input X\Pulse Width
Type
High_Speed_Input_X_Type
Parameter’s CAN Index by Type
Input:
1 = 0x322B 0x00
2 = 0x322C 0x00
None / 0
Frequency / 1
Width – High / 2
Width – Low / 3
Count – Rising / 4
Count – Falling / 5
0
The Type selection will congure this High Speed Input to return
the monitor variables Count, Frequency, or Pulse Width basis.
X = 1 or 2 for the Frequency: High_Speed_Input_X_Type
None = 0: Can be used for encoders. The Count, Frequency, or
Pulse Width variables will not be calculated. Do not
use these any frequency, count or width readings if
this Type parameter is set to None.
Values of 1-5 will set this input accordingly, where one-channel
of the Encoder Input will be used (as long as the corresponding
Encoder X Type is set to None. See the Encoder Inputs section).
Frequency = 1: Always measured from the incoming signal’s rising
edge to rising edge, in Hertz (number of times per
second). Each pulse/rise/drop is “1” count.
Width – High = 2: Measures the Pulse Width of the signals high
portion.
Width – Low = 3: Measures the Pulse Width of the signals low
portion.
Counter – Rising: Count triggers on each rising edge of a pulse.
Counter - Falling: Count triggers of each falling edge of a pulse

Curtis Instruments 1351 Specifications

General

Brand	Curtis Instruments
Model	1351
Category	I/O Systems
Language	English