Here is a snippet of perl code:

open(FH, "<", "/dev/mem");
binmode(FH);
seek(FH,0xff230180,0);  #Fails with bad address

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Here is a snippet of C code:

devmem_fd = open("/dev/mem", O_RDWR | O_SYNC);
bridge_map = (uint32_t*)mmap(NULL, 0x100, PROT_READ|PROT_WRITE, 
    MAP_SHARED, devmem_fd, 0xff230180);
reg = (uint32_t*) bridge_map;
printf("Register contents: 0x08x\n", *reg);
munmap (bridge_map, 0x100);
close(devmem_fd);

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In reply to Re^2: Accessing Memory-mapped I/O by Anonymous Monk
in thread Accessing Memory-mapped I/O by Anonymous Monk

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