mensor PCS 400, Руководство по эксплуатации

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REMOTE OPERATION
This section provides information on two methods
of remote communication with the
PCS 400 ; parallel
operation over the IEEE-488-STD bus, and serial
operation over the RS-232 bus. The operator must
choose which method of remote operation to use
since simultaneous use of both methods is not
practical. All of the commands in the following text
are the bare commands seen by the
PCS 400
stripped of all programming idioms. Depending on
the specific program language used, these com-
mands may have to be preceded by or enclosed in
various symbols for transmission. The
PCS 400
commands are not case-sensitive, i.e., upper and
lower case commands are interpreted the same. A
brief IEEE sample program has been included in
the
Appendix for your convenience.
Device Dependent Messages
Device dependent messages are commands spe-
cific to the
PCS 400
that are sent via a remote port
(parallel or serial). These messages are device de-
pendent because they may not be valid for any other
equipment.
To send a device dependent message to the PCS 400 ,
transmit the message with a prefix of “_PCS4" and
end the message with the selected termination
character. An EOI (see EOI under ‘Command Set’
for a definition) can be sent with the termination
character, but is not required.
IEEE-488-STD (GPIB)
The
PCS 400
can be operated from a remote com-
puter which communicates over the IEEE-488-
STD General Purpose Interface Bus, commonly
referred to as the GPIB. To function in this mode
the host computer must contain a GPIB card and
must be connected to the
PCS 400
with an appro-
priate parallel cable.
Software to install and operate the GPIB along with
programming examples is provided by the manu-
facturer of the GPIB card.
The IEEE-488-STD specification is available from
the Institute of Electrical & Electronics Engineers
Inc., 345 East 47th Street, New York, New York,
10017.
IEEE Capability Codes
SH1 . . . . . . full source handshake capability
AH1 . . . . . full acceptor handshake capability
T6 . talker with serial poll and unaddress if MLA
L4 . . . . . . . . listener with unaddress if MTA
SR1 . . . . . . . . full service request capability
RL1 . . full remote/local capability including LLO
PPO . . . . . . . . . . no parallel poll capability
DC1 . . . . . . . . . . full device clear capability
DT1 . . . . . . . . . full device trigger capability
E2 . . . . . . . . . . . . . . . . tri-state outputs
Device Address
The primary address of the
PCS 400
on the GPIB is
set using the front panel keypad. Select [2nd],
[GPIB]. At the MODIFY INSTRUMENT ADDRESS
prompt, enter a number from 0 through 30 as an
address. Press [=] to install the new address. This
number will be stored in memory and used until it
is changed.
Termination String Character
The termination string for the GPIB is set using the
front panel keypad. Select [2nd] [GPIB] [+]. At the
MODIFY DATA TERMINATION CHARACTER
press [=]. Then with the [+] or [–] key choose the
desired terminator to suit your computer. Press [=]
to enable the new termination character. The ter-
mination string will be stored in memory until it is
again changed.
Service Request
The service request line on the GPIB ( SRQ ) will be
asserted when an error is encountered.
Local Lockout
When the
PCS 400
is in the REMOTE mode, local
lockout ( LLO ) is in effect. The instrument will not
respond to the keypad until returned to the LOCAL
mode by the host computer.
Status Display
The
PCS 400
indicates the status of the GPIB in the
upper right of the display: [R] for REMOTE mode.
GPIB Interface Messages
GPIB interface messages are standardized com-
mands that are a function of the GPIB interface
itself.
The method of sending an interface message to the
PCS 400
is dependent upon the specific computer
PCS 400
REMOTE OPERATION
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