Control Functions
PSI BOX PLUS+ Reference
CLEAR.
Resets All or Specified Devices.
________
___________________________
Purpose.
To send all or selected devices to their pre
__________
determined power on state.
The CLEAR command is used to send bus devices to a
device dependent state. If no device addresses are given then the
PSI BOX uses the universal command DCL to send all bus
devices to their power on state. If one or more device addresses
are specified then those devices are commanded to Listen and
then told to perform a selective device clear.
The PSI BOX asserts ATN and becomes the active
controller, then the IEEE command DCL, or a series of listen
addresses followed by the SDC command, is sent over the IEEE
bus. After the command has been sent the ATN remains true,
PSI BOX is the active controller.
The CLEAR command is a very flexible way to reset
devices to a known state after they have become confused by an
error or after they have been set to an unknown state by a
previous user.
Format.
CLEAR
_________
Params.
None, one or several.
_________
Returns.
None.
__________
Example.
BUS CLEAR
Resets ALL devices
___________
BUS CLEAR 2
Resets device 2
BUS CLEAR 2,3,4
Resets devices 2 3 and 4.
Bus Activity.
___________
_
assert ATN if not already so
DCL
or:
assert ATN if not already so
MTA of PSI BOX
UNL all stop listening
LAG 2 first addresses specified
....
LAG 4 last address specified
SDC addressed device to perform a clear
Chapter 8
Page 89
Содержание P.S.I. BOX
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