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

thnx a lot,

so, are the 'Create New Component' and the 'Interface to User Logic' in SOPC implement an avalon interfaced device or just any general device?

thnx

The interface to user logic will create the avalon interface for your logic.

You'll have to select address width, data bus width, etc. as appropriate.

Regards,

--Scott

I should be more clear ... sorry:

> The interface to user logic will create the avalon interface for your logic.

The interface to user logic will export the avalon bus signals from the

system module that your custom logic connects to.

--Scott