DAEnetIP3
User Manual
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35
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9. Analog Inputs Port (Port C)
Port C is 8 channel analog input port (8 x ADC). The reference voltage is
2.048VDC and each channel is with 10 bit resolution (1024).
9.1.
Port C Web page
Figure 32.
Port C web page
– 8 x analog inputs
9.2.
Reading the analog inputs
Each of the eight analog inputs can be read by any time. The returned value is a
number between 1 and 1023.
Each analog input has software filter. The filter is shown on figure 33.
Figure 33.
Structure of ADC filter
The filter is actually buffer (array) with 8 elements. When the user (or firmware)
reads some analog input value, actually the returned result is the sum of all elements
divided to 8 (the length of the buffer). In this way it is retrieved the average value of
the analog signal and not the moment (which very often may not be correct).
The time interval between two measured values (elements) is determined by the
user. It is called
Refresh time.
The minimum value is 100ms.
So single reading of
the analog input channel may be minimum 0.8 seconds.
The algorithm for filling the buffer is showed on figure 34. This is actually FIFO
(First In First Out) buffer.
