PIO Vs. Avalon ?!

Hi wesam,

> Should I interface it to the processor using the avalon bus or can i

> interface to a PIO block that's already interfaced to the avalon bus?

I started a design using a PIO for address, a PIO for control, and a PIO for

data. I quickly changed my mind once I started writing the device driver

code -- it was much more time-efficient (and MIPS efficient) to just write a

simple avalon interface. Later, I decided I needed DMA support ... and it

basically came "for free" since I already had the avalon interface.

In general, if you're doing more than just twiddling a few bits, you should

consider the avalon interface. One way or another, you'll end up writing the

interface logic anyway-- whether it's in an HDL or in C ... but the HDL

strategy comes with some built-in "freebies" ;-)

Regards,

--Scott