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2 measurement rate: 101 to 600 hz, Figure 76: alarms toggled in bit-shift example – Campbell Scientific CR800 and CR850 Measurement and Control Systems User Manual

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Section 7. Installation

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BeginProg

Scan

(1,Sec,0,0)

'<<<

VoltSe

(FastSE(),1,mV2_5,1,False,100,250,1.0,0)

CallTable

FastSETable

NextScan

EndProg

By modifying the

Interval

,

Units

,

and Buffers

arguments, VoltSE() can be

executed at 100 Hz at 100% duty cycle. The following program measures 16
analog input channels at 100 Hz.

Table 34. CRBasic EXAMPLE. Measuring VoltSE() at 100 Hz

PipeLineMode

'<<<

Public

FastSE(16)

DataTable

(FastSETable,1,-1)

Sample

(16,FastSE(),FP2)

EndTable

BeginProg

Scan

(10,mSec,10,0)

'<<<

VoltSe

(FastSE(),16,mV2_5,1,False,100,250,1.0,0)

CallTable

FastSETable

NextScan

EndProg

7.8.12.2 Measurement Rate: 101 to 600 Hz

To measure at rates between 100 and 600 Hz, the SubScan() / NextSubScan
instruction pair is added. Measurements over 100 Hz do not do not have 100%
duty cycle, but are accomplished through measurement bursts. Each burst lasts
for some fraction of the scan interval. During the remainder of the scan interval,
the CR800 processor catches up on overhead tasks and processes data stored in
the buffers. For example, the CR800 can be programmed to measure VoltSE() on
8 channels at 200 Hz with a 95% duty cycle as follows:

Table 35. Measuring VoltSE() at 200 Hz

PipeLineMode

'<<<

Public

BurstSE(8)

DataTable

(BurstSETable,1,-1)

Sample

(8,BurstSE(),FP2)

EndTable

BeginProg

Scan

(1,Sec,10,0)

'<<<

SubScan

(5,mSec,190)

'<<<

VoltSe

(BurstSE(),8,mV2_5,1,False,100,250,1.0,0)

CallTable

BurstSETable

NextSubScan

NextScan

EndProg