From: Johan Karlsson <k AT sm DOT luth DOT se>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DPMI Physical Address Mapping
Date: Wed, 23 Jul 1997 09:03:45 +0200
Organization: Luleå University of Technology
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Message-ID: <33D5ACD0.4487EB71@sm.luth.se>
References: <199707221500 DOT IAA26323 AT adit DOT ap DOT net>
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CC: brown AT signal DOT dra DOT hmg DOT gb, eldredge AT ap DOT net
To: djgpp AT delorie DOT com
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Nate Eldredge wrote:
> 
> You wrote:
> >/* Map in the board's physical address */
> >my_map->size = 0x01000000;
> >my_map->address = 0x3d000000;
> >
> >if((linear = __dpmi_physical_address_mapping(my_map)) == -1)
> Make that __dpmi_physical_address_mapping(&my_map). The function takes a
> __dpmi_meminfo* argument.
> >       printf("Failed to map physical address\n");
> I bet it'll work now.

That is not the problem here. Since -> is used and not . to access the
struct members it must be a pointer.

However, the misstake is that __dpmi_physical_address_mapping does not
return the linear address. It writes the address into my_map->address.

It should be

if(__dpmi_physical_address_mapping(my_map) == -1)
  printf("Failed to map physical address\n");
linear = my_map->address;



MVH 
Johan Karlsson
mailto:k AT sm DOT luth DOT se
Department of Computer Science and Electrical Engineering
Luleå University of Technology, SWEDEN