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I am new to the use of FPGAs for signal processing as I have only been using dinosaur GPIB, and so I have a few questions about capability.
I need to feed in two time-varying DC voltages, find the difference and take the square root, then multiply by a constant and output the result every microsecond or so. I am assuming that this is a cake walk to program in Quartus and an easy job for even the cheapest FPGA like the Cyclone, is that a fair assumption? Thank you.Link Copied
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it seems quite reasonable by using some pipeline registers and a word size not too big, say, not longer than 32 bits and fixed point arithmetic, anyway, if you use Altera's Megafunctions (lpm_add_sub, altsqrt and lpm_mult) clock frequency could be significantly higher than 1 MHz.
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Uh, you do know that you need a ADC though right. There are no built-in ADCs in the FPGA. So you'll need an external ADC to do the voltage sampling.
Jake- Mark as New
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Once you have your data flow in your mind, you could as parrdo already mentioned, use the altera megafunctions to implement the needed data processing and wire the stuff up on schematics top level or use vhdl or verilog hdl or altera hdl.
so you need a modul that reads out an ADC at a constant rate, feed the value into the next modul that calculates the difference between the actual and the last ADC, and so on ... you can to this with purely fsm to get an acurate time constant measument or use a smal cpu like nios if you need to process your data a bit more and send them via any kind of interface. but of course you could also do this without any cpu. an fpga can do so many things at the same time, yes at the same clock cycle. if you want, you can get an FFT of your input samples to see what frequency causes your voltage changes :-) The fft won't disturb your sampling rate of 1 MSPS.
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