On Sat, 9 Nov 1996, Taras Ivanenko wrote:

> > I've tracked it down to rouine iteattach() in ite.c, where it seems that 
> > the call to pmap_extract() returns zero, which of course won't match the 
> > value for conspa.
> 
> As far as I can tell, pmap_extract() returns zero when asked to
> extract the adress which is already physical, i.e. mapped to
> itself. In your case internal video is probably mapped to physical I/O
> address, therefore zero.

pmap_extract() returns 0 if either the pmap to extract the address from
isn't valid or if the address hasn't been mapped.  However, there is also
the case where physical address corresponding to the VA we give
pmap_extract() is actually 0, also.  The latter is the case on the IIci,
where the physical address of the internal video framebuffer is 0 (see
Guide to the Macintosh Family Hardware, 3rd ed., pp 221 and 412).

Paul, what is the value of conspa that you're seeing when you have a
display connected to the internal video connector?  Is the Booter properly
passing in the address of the appropriate framebuffer?

--scott