Lakeshore 332, Руководство пользователя

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Lake Shore Model 332 Temperature Controller User’s Manual
6.1.1 Changing IEEE-488 Interface Parameters
Two interface parameters, address and terminators, must be set from the front panel before
communication with the instrument can be established. Other interface parameters can be set with
device specific commands using the interface (Paragraph 6.3).
Press the
Interface
key. The first screen is for selecting the Serial Interface Baud Rate, and can be
skipped by pressing the
Enter
key. The Address screen is then displayed as follows.
Select − With − °®
IEEE − Address −− 12
Press the
s
or
t
keys to increment or decrement the IEEE Address to the desired number. Valid
addresses are 1 thru 30. Default is 12. Press
Enter
to accept new number or
Escape
to retain the
existing number. Pressing
Enter
displays the Terminators screen.
Select − With − °®
IEEE Term −− Cr − Lf
Press the
s
or
t
keys to cycle through the following Terminator choices: CR/LF, LF/CR, LF, and
EOI. The default is Cr Lf. To accept changes or the currently displayed setting, push
Enter
. To cancel
changes, push
Escape
.
6.1.2 IEEE-488 Command Structure
The Model 332 supports several command types. These commands are divided into three groups.
1.
Bus Control
– Refer to Paragraph 6.1.2.1.
a. Universal
(1) Uniline
(2) Multiline
b. Addressed Bus Control
2.
Common
– Refer to Paragraph 6.1.2.2.
3.
Device Specific
– Refer to Paragraph 6.1.2.3.
4.
Message Strings
– Refer to Paragraph 6.1.2.4.
6.1.2.1 Bus Control Commands
A Universal Command addresses all devices on the bus. Universal Commands include Uniline and
Multiline Commands. A Uniline Command (Message) asserts only a single signal line. The Model
332 recognizes two of these messages from the BUS CONTROLLER:
Remote (REN)
and
Interface Clear (IFC)
. The Model 332 sends one Uniline Command:
Service Request (SRQ)
.
REN (Remote)
– Puts the Model 332 into remote mode.
IFC (Interface Clear)
– Stops current operation on the bus.
SRQ (Service Request)
– Tells the bus controller that the Model 332 needs interface service.
A Multiline Command asserts a group of signal lines. All devices equipped to implement such
commands do so simultaneously upon command transmission. These commands transmit with the
Attention (ATN) line asserted low. The Model 332 recognizes two Multiline commands:
LLO (Local Lockout
) – Prevents the use of instrument front panel controls.
DCL (Device Clear)
– Clears Model 332 interface activity and puts it into a bus idle state.
6-2 Remote Operation