Messages in this thread | | | Date | Sat, 27 Jan 2001 12:47:59 -0800 | From | "H. Peter Anvin" <> | Subject | Re: Linux Post codes during runtime, possibly OT |
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Rogier Wolff wrote: > > H. Peter Anvin wrote: > > Followup to: <3A709E99.25ADE5F6@echostar.com> > > By author: "Ian S. Nelson" <ian.nelson@echostar.com> > > In newsgroup: linux.dev.kernel > > > > > > I'm curious. Why does Linux make that friendly 98/9a/88 looking > > > postcode pattern when it's running? DOS and DOS95 don't do that. > > > > > > I'm begining to feel like I can tell the system health by observing it, > > > kind of like "seeing the matrix." > > > It output garbage to the 80h port in order to enforce I/O delays. > > It's one of the safe ports to issue outs to. > > Yes, because it is reserved for POST codes. You can get "POST > debugging cards" that simply have a BIN -> 7segement encoder and two 7 > segment displays on them. They decode 0x80. That's what it's for. >
Again, if you want to change it, find another safe port, test the hell out of it, an *PUBLICIZE IT* so noone will use it in the future.
-hpa
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