Programming Example - Program And Read Register Set; Queues; Output Queue - Keithley 2500 User Manual

Models 2500 and 2502 User's Manual

Programming example - program and read register set

The command sequence in
Registers are read using the binary format (which directly indicates which bits are set).
The command to select format (FORMat:SREGister) is documented in
Table 14-8
Program and read register programming example
FORM:SREG BIN
STAT:MEAS:ENAB 512
STAT:MEAS:COND?
STAT:MEAS?

Queues

The Model 2500 uses two queues, which are first-in, first-out (FIFO) registers:
• Output Queue — Used to hold reading and response messages.
• Error Queue — Used to hold error and status messages. (See
The Model 2500 status model
the other registers.

Output queue

The output queue holds data that pertains to the normal operation of the instrument. For
example, when a query command is sent, the response message is placed in the output
queue.
When data is placed in the output queue, the Message Available (MAV) bit in the status
byte register sets. A data message is cleared from the output queue when it is read. The
output queue is considered cleared when it is empty. An empty output queue clears the
MAV bit in the status byte register.
A message is read from the output queue by addressing the Model 2500 to talk after the
appropriate query is sent.
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176
TestEquipmentDepot.com
Table 14-8
Command
Select binary format to read registers.
Enable BFL (buffer full).
Read Measurement Condition Register.
Read Measurement Event Register.
(Figure
programs and reads the measurement register set.
Description
14-1) shows how the two queues are structured with
Status Structure 14-19
Table 14-2.
Appendix B.)