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Altera_Forum
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15 years ago

Sampling using the VIC

I want sample the output of an ADC and store it in registers where it can be processed while another sample is taken. After reading through some Nios literature, it seems like the best way to do thi...
Altera_Forum's avatar
Altera_Forum
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15 years ago

@vogels

dc filter is a special case of high pass filter.

for dc removal I can think of one well known 1st order IIR filter:

Hz = (1- z-1)/(1-az-1)

in matlab:

num =[1 -1];

den =[1 -a]; where a = fraction e.g. 0.95

This is in effect running average subtractor.

example: your input is 8 bits. you accumulate say 1024 samples in a large enough adder(18 bits) then take 8 MSBs of adder result to subtract it from input in a feedback loop.