On 5/20/05, Eric Smith <[EMAIL PROTECTED]> wrote: > Timothy wrote: > > Is B==MDA and D==CGA? > > Yes. > > > Ok, here's the logic to decode VGA I/O addresses... let me know if it's > > right: > > > > reg VGAI_v; > > always @(address_last or VGAI_en or MDA_en or CGA_en) begin > > case (address_last[6:0]) > > 'h34, 'h35, 'h3a: VGAI_v = VGAI_en && MDA_en; > > 'h54, 'h55, 'h5a: VGAI_v = VGAI_en && CGA_en; > > 'h40, 'h41, 'h42, 'h44, 'h45, 'h47, 'h48, 'h49, 'h4a, > > 'h4c, 'h4e, 'h4f: VGAI_v = VGAI_en; > > default: VGAI_v = 0; > > endcase > > VGAI_v = VGAI_v && (address_last[31:7] == 7); > > end > > I think that's mostly right. 'h43 and 'h46 should be added to the > third case, or the subsystem enable and PEL mask registers.
I left them out because they're not on the wiki. Anyhow, I added them. > > It may be OK to add 'h4b and 'h4d as well; I haven't been able to find > any evidence of I/O devices that map to 3CB or 3CD. Just to be safe, I'll leave them out. _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
