NAME

mem, kmem, vme16d16, vme24d16, vme32d16, vme16d32, vme24d32, vme32d32, mbmem, mbio, − main memory and bus I/O space

SYNOPSIS

None; included with standard system. 

DESCRIPTION

These devices are special files that map memory and bus I/O space.  They may be read, written, seek’ed and (except for kmem) mmap(2)’ ed.

Mem is a special file that is an image of the physical memory of the computer.  It may be used, for example, to examine (and even to patch) the system. 

Kmem is a special file that is an image of the kernel virtual memory of the system. 

vme16d16 (also known as vme16) is a special file that is an image of VMEbus 16-bit addresses with 16-bit data. Vme16 address space extends from 0 to 64K. 

vme24d16 (also known as vme24) is a special file that is an image of VMEbus 24-bit addresses with 16-bit data. Vme24 address space extends from 0 to 16 Megabytes.  The VME 16-bit address space overlaps the top 64K of the 24-bit address space. 

SUN-3 VMEBUS ONLY

vme32d16 is a special file that is an image of VMEbus 32-bit addresses with 16-bit data. 

vme16d32 is a special file that is an image of VMEbus 16-bit addresses with 32-bit data. 

vme24d32 is a special file that is an image of VMEbus 24-bit addresses with 32-bit data. 

vme32d32 (also known as vme32) is a special file that is an image of VMEbus 32-bit addresses with 32-bit data. Vme32 address space extends from 0 to 4 Giggabytes.  The VME 24-bit address space overlaps the top 16 Megabytes of the 32-bit address space. 

vme∗ type special files can only be accessed in VME based systems. 

SUN-2 MULTIBUS ONLY

Mbmem is a special file that is an image of the Multibus memory of the system.  Multibus memory is in the range from 0 to 1 Megabyte.  Mbmem can only be accessed in Multibus based systems. 

Mbio is a special file that is an image of the Multibus I/O space.  Multibus I/O space extends from 0 to 64K.  Mbio can only be accessed in Multibus based systems. 

When reading and writing mbmem and mbio odd counts or offsets cause byte accesses and even counts and offsets cause word accesses. 

FILES

/dev/mem
/dev/kmem
/dev/mbmem
/dev/mbio
/dev/vme16d16
/dev/vme16
/dev/vme24d16
/dev/vme24
/dev/vme32d16
/dev/vme16d32
/dev/vme24d32
/dev/vme32d32
/dev/vme32

Sun Release 3.2  —  Last change: 18 September 1985