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Altera_Forum's avatar
Altera_Forum
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12 years ago

Reading external data using On-chip FIFO and NIOS II

Hi all, I'm trying to read a 8-bit ADC with parallel output using NIOS II. I need to read the ADC at 24MHz to capture correct samples. I have been trying a 1K On-Chip FIFO to capture this data....
Altera_Forum's avatar
Altera_Forum
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12 years ago

Maybe set your ALMOST_FULL threshold significantly lower?

If it is a 1024 deep FIFO, and you set the threshold to 1000, then you only have (24) clocks to service the FIFO before it will fill. If you're pushing FIFO data at 24MHz and NIOS is running at 100MHz, then maybe you have around 100 clocks --- which is not a lot of time.