12-01-2011 02:57 PM
Hi,I have an avalon-ST source streaming data into a onchip FIFO (ST input & MM output). Currently the Nios reads blocks of data using a call to 'altera_avalon_fifo_read_fifo()' and places it into an array to perform a computation. At the first call, the FIFO is already filled up. After processing a block or two it catches up and I am reading zero between valid data samples. First question - is there a way to empty the contents of my onchip FIFO without reading out the data? Alternatively, can the FIFO be disabled by default until the Nios enables it through a status register? Second question - without using interrupts, can I make a blocking call to read the fifo? In other words, how can I force the Nios to wait until the FIFO has a new data sample? Thanks, -J
12-02-2011 07:44 PM
It doesn't look like the FIFO supports flushing. By disabling do you mean disable it from accepting streaming data until enabled? If so then it doesn't look like it supports that either.Normally I build my own FIFOs when I need additional functionality. Luckily they are easy to build so maybe that would be your best bet to do.