shithub: 9ferno

ref: 6966e8d72ae8fb72ebf98909acbd464aff84a3cc

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.TH SWITCH 3 MPC8xx
.SH NAME
switch \- hardware option switch
.SH SYNOPSYS
.nf
.B bind -a '#r' /dev

.B /dev/switch
.fi
.SH DESCRIPTION
.PP
The switch device serves a one-level directory,
giving access to one read-only file,
.BR switch .
A read returns the value of the development board's
option switch (DS1), represented as a decimal number
from 0 to 15, representing four bits,
each corresponding to one of the four toggles.
Each toggle produces the value 0 when it
is set `ON' and 1 when it is off.
Toggle 1 corresponds to bit
.B 1<<3
in the number,
toggle 2 corresponds to bit
.BR 1<<2 ,
and so on
.SH SOURCE
.B /os/mpc/devrtc.c