81h BT$TOFF temporary switchoff
Input D register - No. of seconds to be off for (2-1800)
Output - none -

Provides a temporary off facility.

The machine will switch of for the number of seconds in the D register before automatically switching back on and returning from BT$TOFF.

The maximum time to be off is 1800 seconds (30 minutes) since the system clock must be updated. The routine can, of course, be called repeatedly to 'apparently' switch off for longer times.

This call is not available on CM/XP machines.

Example Switch the machine off for 12 hours.
        LDAA    #24             ;24 1/2 hours needed
LOOP:   LDD     #1800           ;to switch off for 30 minutes
        OS      BT$TOFF
        BNE     LOOP            ;repeat 24 times
Errors - none -