Device Selector - Agilent Technologies 4288A Programming Manual

Required equipment
1. 4288A with accessories for measuring DUTs
2. External controller (computer)
The external controller can be any personal computer or workstation with a GPIB
interface card and the appropriate software (such as HTBasic) for controlling the
instrument via the GPIB interface.
3. Other hardware as needed (extra instruments and/or peripherals)
4. GPIB cables for connecting the 4288A to the external controller and other hardware
Possible sizes and configurations of your remote control system
• One GPIB system can host up to 15 devices.
• Device-to-device cables should be no longer than 4 m. The total length of connection
cables used in one GPIB system should not exceed 2 m × N, where N is the number of
connected devices (including controller). In any case, do not construct a system whose
total cable length exceeds 20 m.
• Do not connect any single device with more than four connectors. Doing so exposes the
connectors to excessive strain, possibly causing a failure.
• The topology of device connections can be star, linear, or a combination of them. Loop
connections are not supported.

Device selector

Each device is assigned a unique identifier called the "device selector." When the
controller attempts to control (communicate messages with) one of the devices connected
over the GPIB remote control system, it selects that device with the appropriate device
selector.
A device selector consists of a select code (normally 7) and a GPIB address. For example,
when the select code is 7 and the GPIB address is 17, the device selector is 717. The select
code is system-global. Each device in the same system is assigned a GPIB address that
uniquely identifies it. When this document refers to a device selector in descriptive text or
sample programs, it is always assumed to be 717. Use the following procedure to set the
GPIB address of the 4288A.
Chapter 2
Overview of Remote Control
Setting Up a GPIB Remote Control System
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