NIOS is generating Read Signal Twice.

Hi, Cris,

Thanks for your kind information, my issue get resolved. I took 32 bit bus from NIOS and mapped the Lower 16 bit with custom interface.

Thanks a lot to all replies.

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The misunderstanding is related to the fact that NIOS always performs 32bit read accesses, even if you explicitly use IORD_16DIRECT or IORD_8DIRECT: in these cases you'll always get multiple CS and RD strobes.

This can be annoying if your external address is a fifo or some register which is supposed to change at every read access.

The solution I used in a similar case is using a 32bit external data bus and connecting only the 8 or 16 bits I need; this way I always perform a single 32bit access and discard extra bits.

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