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Altera_Forum's avatar
Altera_Forum
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15 years ago

dataavailable signal on Avalon MM

I have a MM slave that has to read an external device, and due to the latency in the read process to this device, I would like to have my Nios initiate the process by a write to a register and then r...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Hi,

"dataavailable" is part of the optional (and deprecated) flow control feature.

It doen's quite do what you want and it was never supported by NIOS anyway -- NIOS will simply "ignore" the signal.

What you need to do is either

a) start the process by writing to a register and then poll (read) a status register to see if it has been completed

b) start the process by writing to a register and then generate an interrupt when it has been completed