Series 2280 Precision DC Power Supply Reference Manual
Appendix D: Status model
077085503 / March 2019
D-7
Status byte and service request
The Status Byte Register monitors the registers and queues in the status model and generates
service requests (SRQs).
When bits are set in the status model registers and queues, they generate summary messages that
set or clear bits of the Status Byte Register. You can enable these bits to generate an SRQ.
Service requests (SRQs) instruct the controller that the instrument needs attention or that some event
has occurred. When the controller receives an SRQ, the controller can interrupt existing tasks to
perform tasks that address the request for service.
Status Byte Register
The Status Byte Register consists of two 8-bit registers that control service requests, the Status Byte
Register, and the Service Request Enable Register. These summary bits do not latch, and their
states (0 or 1) are solely dependent on the summary messages (0 or 1). For example, if the Standard
Event Register is read, its register will clear. As a result, its summary message will reset to 0, which
then will reset the ESB bit in the Status Byte Register. These registers are shown in the following
figure.
