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No. 99MBC071A
6. INTERFACE UNIT
6.2.4.5 Operations
1) The GP-IB interface unit for the LSM is basically a listener that receives various com-
mands, and a talker that transmits response commands. For further information on recep-
tion commands and response commands, refer to the description in Sec. 6.1.2.4.
2) When receiving an IFC (Inter Face Clear), the GP-IB interface is initialized.
• Remote state will be canceled to local state.
• Local lockout state (LLO) will be canceled.
• Service request (SRQ) transmission will be disabled.
3) When the GP-IB interface receives an REN (Remote ENable) signal followed by other
commands, the interface enters the remote state. In the remote state, only the
C
key
can be operated.
4) When the GP-IB interface receives an REN (Remote ENable) signal followed by an LLO
(Local LOckout) as a multi-statement, the interface enters into local lockout state. In this
local lockout state, all the key operations are prohibited.
(This state can be released by inputting an IFC (Inter Face Clear) from the host computer.)
5) However in the remote state or local lockout state, I/O operations, except for key entries,
will operate as usual.
6) When the GP-IB interface receives a GET command as a multi-statement, the single-run
measurement or zero-run measurement will commence.
Zero-run measurement can be terminated by inputting another GET command.
7) This interface unit (as a talker) does not output unless a transmission command has been
received.
8) When this interface unit receives an SRQ command, it is ready to transmit the service
request and the SRQ lamp lights.
• When this interface transmits a response (sending data from this interface), send a
service request signal (SRQ) to ready the controller for data reception.
• When the GP-IB interface receives an SPE (Serial Poll Enable) from the controller, the
interface outputs the SRQ status byte on the data bus, which describes the content of
the request.
• In the service request state, the interface does not output the OK or ER0 – 7 commands
as a response command, but only sends the SRQ status byte to describe the conditions.
9) Just after power on transmit a “CL” command as the first communication command and
repeat this until a response of “OK” is received.
