Developing a self made Tri-State Slave

Hello,

For speeding up the transfer between the DM9000 Ethernet Controller and the Nios II I wanted to use dynamic bus sizing. Unfortunately a read transfer of only 16-bit is not supported in the way I want (see mnl_avalon_bus.pdf, Page 98). I read the thread “Dynamic Bus Sizing on Avalon Bus” (http://www.niosforum.com/forum/index.php?act=st&f=2&t=790) but it seems that my knowledge is not enough to bring that stuff to work.

My configuration is as follows: The Nios II system is equipped with an “Avalon Tri-State Bridge”. A CompactFlash, a Flash and the Ethernet Controller are connected to the bridge. The data bus width is 16-bit (there were no more pins left). I think the best would be to develop a self-made Tri-State Slave which is connected to the bridge. But I don’t know how to do this.

What do you think?

Regards,

niosIIuser

PS: I’m working with Quartus II 5.0 and Nios II 5.0.