Hioki 9518-02, Instruction Manual

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4.11 Status Model
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Generation of service request (SRQ)
MSS
RQS
ESB MAV ESB0
bit 7
bit 6
bit 5 bit 4 bit 3 bit 2 bit 1 bit 0
Logical sum ＆ ＆
ESB0
bit 3 bit 2 bit 1 bit 0
ESB MAV
bit 5 bit 4
×
bit 7 bit 6
Represents standard event register
Data is present in the output queue
Represents corresponding event register
＆
Status byte register (STB)
Service request enable register (SRER)
Generation of service requests
4.11 Status Model
In its implementation of the serial polling function using service requests, the
3157 employs the status model specified by IEEE 488.2.
The term "event" refers to any phenomenon which generates a service request.
The status byte register holds information relating to the event registers and
the output queue.
It is further possible to use the service request enable register as a mask to
select the items required. If any of the bits selected by the mask becomes 1,
bit 6 (the master summary status or MSS bit) is also set to 1, an RQS
message is generated, and this generates a service request.