137
A maximum separation of 4 m between any two devices and an average
separation of 2 m over the entire bus.
A maximum total cable length of 20 m.
No more than 15 device loads connected to each bus, with no less than two-thirds
powered on. For example 1 GPIB controller and a maximum of 14 GPIB
instruments.
NOTE:
A bus extender, which is available from numerous manufacturers, is
available to overcome these limitations.
8.2.2 GPIB Address
Each device on the GPIB (IEEE-488) interface must have a unique address. You can
set the address of the HypotULTRA to any value between 0 and 30. The address can
only be set from the front panel. The address is stored in non-volatile memory and
does not change when the power has been off or after a remote reset.
The address is set to 8 when the instrument is shipped from the factory.
8.3 Interface Functions
The capability of a device connected to the bus is specified by its interface functions.
These functions provide the means for a device to receive, process, and send
messages over the bus. The interface functions are listed in the chart below.
GPIB 488.1 INTERFACE FUNCTIONS
INTERFACE
FUNCTION
SUBSET
DESCRIPTION
Source Handshake
SH1
Complete Source handshake capability
Acceptor Handshake
AH1
Complete Acceptor handshake capability
Talker
T6
Talker functions (unaddress if MLA)
Listener
L4
Listener functions (unaddress if MTA)
Service Request
SR1
Complete Service request capability
Remote Local
RL0
No remote/local capability
Parallel Poll
PP0
No parallel poll capability
Device Clear
DC1
Complete Device clear capability
Device Trigger
DT0
No device trigger capability
Controller
C0
No controller capability
Electrical Interface
E2
Three-state drivers
Controllable Items
Test and Reset control.
Setting of test parameters for tests.
Reading of instrument status and test results.
Data Codes
ASCII
Delimiter
NL (+ EOI)
Содержание HypotULTRA 7800
Страница 25: ...20 0 00 10 00 0 01 2 of reading 2 counts Additional error when reading 6 of range 0 2 of range ...
Страница 34: ...29 ...
Страница 53: ...48 ...
Страница 121: ...116 ...
Страница 128: ...123 ...
Страница 143: ...138 ...
Страница 187: ...182 ...
Страница 196: ...191 Calibration of 9 99mA DC Current Range The 10mA DC current range calibration is a one step process ...
Страница 202: ...197 Calibration of GFI 5 0mA The calibration of GFI 5 0mA is a two step process ...