Rohde & Schwarz R&S FSP Series, Руководство по эксплуатации

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R&S FSP Maintenance and Instrument Interfaces
Instrument Interfaces
8.4 Operating Manual 1164.4556.12 - 06
Handshake bus with three lines.
DAV (Data Valid),
active low signals a valid data byte on the data bus.
NRFD (Not Ready For Data),
active low signals that one of the devices connected is not ready for data transfer.
NDAC (Not Data Accepted),
active low as long as the device connected is accepting the data present on the data
bus.
8.3.1.3 Interface Functions
Instruments which can be remote controlled via the GPIB can be equipped with dif-
ferent interface functions. The table below lists the interface functions appropriate
for the instrument.
8.3.1.4 GPIB Messages
The messages transferred via the data lines of the GPIB can be divided into two
groups:
– “Interface Messages” on page 8.4
– “Instrument Messages” on page 8.5
Interface Messages
Interface messages are transferred on the data lines of the GPIB when the "ATN"
control line is active (LOW). They are used for communication between controller
and instruments and can only be sent by the controller which currently has control of
the GPIB.
Universal Commands
The universal commands are encoded 10 - 1F hex. They affect all instruments con-
nected to the bus without addressing.
Control character Interface function
SH1 Handshake source function (source handshake), full capability
AH1 Handshake sink function (acceptor handshake), full capability
L4 Listener function, full capability, unaddress if MTA.
T6 Talker function, full capability, ability to respond to serial poll, unaddress if MLA
SR1 Service request function (Service Request), full capability
PP1 Parallel poll function, full capability
RL1 Remote/Local switch over function, full capability
DC1 Reset function (Device Clear), full capability
DT1 Trigger function (Device Trigger), full capability
C0 No controller function