.TH IO 1
.SH NAME
io \- access PC I/O registers
.SH SYNOPSIS
.B io
[
.B -WLMErw
]
.I address
[
.I value
]
.SH DESCRIPTION
.I io
accesses PC I/O space.
The operation to be performed is selected with
.B -r
or
.B -w
for reading or writing, respectively.
The default operation size is a byte.
C style notation for integers (e.g.
.B 0x42
or
.BR 023 )
is accepted for the
.I address
and
.I value
parameters.
.PP
.TP
.B  -W
Perform a word (16 bit) operation.
.TP
.B  -L
Perform a long / double word (32 bit) operation.
.TP
.B  -M
Access a 64 bit wide machine specific register (MSR).
.TP
.B  -E
Access embedded controller space.
.SH SOURCE
.B /sys/src/cmd/io.c
.SH SEE ALSO
.IR seg (1),
.IR arch (3)
.SH HISTORY
.I Io
first appeared in 9front (April, 2011).