Keithley 707B, Справочное руководство

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Models 707B and 708B Switching Matrix Reference Manual Appendix C: Status model
707B-901-01 Rev. A / August 2010 C-19
Enable and transition registers
In general, there are three types of user-writable registers that are used to configure which bits feed
the register summary bit and when it occurs. The registers are identified in each applicable Instrument
Control Library command table and defined as follows:
•
Enable register (identified as .enable in each attributes command listing): allows various
associated events to be included in the summary bit for the register.
•
Negative-transition register (identified as .ntr in each attributes command listing): a particular
bit in the event register will be set when the corresponding bit in the NTR is set, and the
corresponding bit in the condition register transitions from 1 to 0.
•
Positive-transition register (identified as .ptr in each attributes command listing): a particular bit
in the event register will be set when the corresponding bit in the PTR is set, and the
corresponding bit in the condition register transitions from 0 to 1.
Controlling node and SRQ enable registers
Attributes to control system node and SRQ enable bits and read associated registers are summarized
in the Status register sets which are summarized in the
Status Byte register overview (on page C-4).
For example, either of the following will set the system node QSB enable bit:
status.node_enable = status.QSB
status.node_enable = 8
TSP-Link system status
The TSP-Link is an expansion interface that allows the instruments to communicate with each other.
The test system can be expanded to include up to 32 TSP-Link enabled instruments. In a TSP-Link
system, one node (instrument) is the master and the other nodes are the subordinates. The master
can control the other nodes (subordinates) in the system. See
TSP-Link system and running parallel
test scripts (on page 6-45) for details on the TSP-Link.
The system summary registers, shown in Status Byte register overview (on page C-4) and System
summary bit (System register) (on page C-5), are shared by all nodes in the TSP-Link system. A
status event that occurs at a subordinate node can generate an SRQ (service request) in the master
node. After detecting the service request, your program can then branch to an appropriate subroutine
that will service the request. See
Status byte and service request (SRQ) (on page C-15) for details.
Status model configuration example
The following example illustrates the status model configuration for a TSP-Link system. In this
example, a Node 15 thermal aspect event will set the RQS bit of the Status Byte of the master Node.