ETS-Lindgren 2090 Controller - Manual (Page 82)

Using the GPIB Command Set with the Model 2090 Model 2090 Multi-Device Controller
GPIB STATUS REPORTING
The Model 2090 supports the ANSI/IEEE 488.2 Standard
Interface Protocols for GPIB interfaces. As such, it is
capable of reporting various device status conditions and
requesting service over the GPIB. When used properly,
these capabilities allow programmers to develop powerful
applications that can handle almost any condition the
controller may encounter.
The status reporting method centers around a set of binary
registers whose bits are logical flags which indicate the
status of various instrument states and error conditions.
Each status register is associated with an enable register
which allows the user (program) to configure which status
flags will generate requests for service from the controller.
The primary status register is the Status Byte Register. If
the bits of this register, when logically ANDed with the bits
of the Service Request Enable Register, are non-zero, a
Service Request (SRQ) is issued to the Controller-in-
Charge (CIC) of the GPIB (that is normally the computer
running a program). Each bit of the Status Byte Register
indicates the status of other status registers and their enable
registers, as well as certain queues. These registers include
the Standard Event Status Register, the Device Dependent
Error Register, and the Output Queue. Refer to “Appendix
A, Model 2090 GPIB Command Reference”, for more
details on each of these registers. The format of these
registers is laid out in the following figure:
82 © ETS-Lindgren– April, 2006
Revision G– P# 399199