Communicating over the bus
Because HP-IB can address multiple devices through the same interface card,
the device address passed with the program message must include not only
the correct interface select code, but also the correct instrument address.
Interface Select Code (Selects Interface)
Each interface card has a unique interface select code. This code is used by
the controller to direct commands and communications to the proper
interface. The default is typically “7” for HP-IB controllers.
Instrument Address (Selects Instrument)
Each instrument on an HP-IB must have a unique instrument address
between decimal 0 and 30. The device address passed with the program
message must include not only the correct instrument address, but also the
correct interface select code.
DEVICE ADDRESS = (Interface Select Code * 100) + (Instrument
Address)
For example, if the instrument address for the logic analyzer is 4 and the
interface select code is 7, when the program message is passed, the routine
performs its function on the instrument at device address 704.
Logic Analyzer Device Address
The examples in this manual and in the online
HP 54620A/C Programmer’s
Reference assume the logic analyzer is at device address 707.
See the documentation for your HP-IB interface card for more information
about select codes and addresses.
Programming over HP-IB
Communicating over the bus
38
Summary of Contents for 54620A
Page 6: ...6 ...
Page 9: ...1 Introduction to Programming ...
Page 21: ...2 Programming Getting Started ...
Page 35: ...3 Programming over HP IB ...
Page 40: ...40 ...
Page 41: ...4 Programming over RS 232 C ...
Page 48: ...48 ...
Page 49: ...5 Programming and Documentation Conventions ...
Page 53: ...Programming and Documentation Conventions The command tree 53 ...
Page 60: ...60 ...
Page 61: ...6 Status Reporting ...
Page 63: ...Status Reporting Data Structures Figure 4 Status Reporting 63 ...
Page 68: ...68 ...
Page 69: ...7 Installing and Using the Programmer s Reference ...
Page 76: ...76 ...