Jetter JetWeb JX2-CNT1, User Manual

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12.1 Sample Program
JetWeb
78 Jetter AG
The time interval is set to a multiple of 10 ms via time base. For value 1 this means
that the number of increments which have been counted within 10 ms are displayed
as frequency value.
12.1 Sample Program
The speed of an SSI encoder is to be measured by a JX2-CNT1 which is located at
the first I/O position after the basic device. This encoder has a position resolution of
4096 increments. The time interval for frequency measurements is set to 1 second.
This makes the readings more stable as minor fluctuations in frequency
measurements will have no great impact.
JetSym - Symbol Listing
JetSym - Program Listing
Status bit 12 = 1
Register 3xx1: Frequency - Time Base
Function Description
Read Present time interval of frequency measurement
Write New time interval
Value range 1 ... 255 [10 ms]
Value following reset 10 (= 100 ms)
********** Registers *************
rmStatusControl 3003 ; Status / Controller
rmFrequency 3007 ; Frequency value
rmTimeBase 3001 ; Frequency - time base
rRPM 100 ; Speed in RPM
;********** Bit Symbols *************
nbSelectFrequency 12 ;
;
Bit for selecting the
frequency display
...
; +++ Frequency Measurement Initiali++
BIT_SET (rmStatusControl, nbSelectFrequency)
REGISTER_LOAD (rmTimeBase, 100) ; time interval to 1 s
BIT_CLEAR (rmStatusControl, nbSelectFrequency)
...
; +++ Speed Calcu+++
; +++ is executed at regular int++
BIT_SET (rmStatusControl, nbSelectFrequency)
REG rRPM = REG rmFrequency * 60 / 4096
BIT_CLEAR (rmStatusControl, nbSelectFrequency)
...