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Altera_Forum
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16 years ago

transfer from nios to 64-bit component

Hello, I am currently working on my own slave component. I've written and tested the 32-bit input version and it worked well. Now I have 64-bit input version. I know that nios cpu handles 32-...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Jason,

You don't set byteenable -- it's done for you automatically by the master/fabric. Your slave just has to handle it properly.

A 64 bit transfer will look much like you described it.

First, your NIOS program issues a 32 bit write to SLAVE_ADDR+0x0.

Your slave will see a write to 0x0 with byteenable set to 0000_1111.

Next, your NIOS program issues another 32 bit write to SLAVE_ADDR+0x4.

Your slave will see a write to 0x0 with byteenable set to 1111_0000.