Re: On I/O and meory address space

["John R Pierce" <pierce@hogranch.com>]

> 1- How difficult really is it to debug the device driver of a PCI device
> mapped anywhere on a 32 bit memory address space?

In DOS its a beating.  Any other environment, no big deal.
 
> 3- Based on your experience and based on the available products, which one
> of the above three methods are more common (map the registers anywhere in a
> 32 bit address space, map to I/O, implement an indirect addressing scheme,
> and maybe 
> a fourth one: map registers to memory below 1 Meg)? (Personnaly I prefer to
> do the perfect thing rather than the common one. But this is not always the
> appropriate criterion to make the design based on.)

With your 1K byte address space, I'd lean towards doing the indirect addressing
for IO, AND a linear mapping of all the space
 
-jrp
{°