R&S ESU
8.3.1.1
Interface Characteristics
•
8-bit parallel data transfer
•
bi-directional data transfer
•
three-line handshake
•
high data transfer rate
•
up to 15 instruments can be connected
•
maximal length of the interconnecting cables 15 m (single connection, 2m)
•
wired-OR connection if several instruments are connected in parallel.
LOGIC GND
Fig. 8.49 Pin assignment of GPIB interface
8.3.1.2
Bus Lines
Data bus with 8 lines DIO 1 to DIO 8.
The transmission is bit-parallel and byte-serial in the ASCII/ISO code. DIO1 is the
least significant, DIO8 the most significant bit.
Control bus with 5 lines.
IFC (Interface Clear),
active low resets the interfaces of the devices connected to the default setting.
ATN (Attention),
active low signals the transmission of interface messages
inactive high signals the transmission of device messages.
SRQ (Service Request),
active low enables a device connected to send a service request to the controller.
REN (Remote Enable),
active low permits the switch over to remote control.
EOI (End or Identify),
has two functions in connection with ATN:
active low marks the end of data transmission when ATN=high
active low triggers a parallel poll when ATN=low.
Operating Manual 1302.6163.12 - 03
ATN
IFC
NRFD
SHIELD
SRQ
NDAC
12
24
GND(10) GND(8)
GND(11)
GND(9)
GND(7)
Maintenance and Instrument Interfaces
EOI
DIO3
DIO1
DAV
DIO4
DIO2
1
13
GND(6)
DIO8 DIO6
REN
DIO7 DIO5
Instrument Interfaces
8.3