ST2523 Series Operation Manual Ver1.2
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SERVICE REQUEST
When ST2523 requires the controller to execute a task, it will send out a SRQ service request control
signal. SRQ, deemed as an interruption, will inform the controller to prepare the transmitted data or
that errors exist on the instrument. As soon as ST2523 sends a SRQ service request signal, it will set
the status byte to 6. 6 bytes are RQS request service bytes and sometimes connects with serial poll to
act as the status byte. When ST2523 enables the SPOLL command, it will clear the RQS request
service bit and the SRQ string. Each bit in a status byte will enables a SRQ service request. User can
shield the status byte to judge which bit causes ST2523 to set SRQ. For details, see “Status Byte”.
TRIGGER (GET)
Trigger bus command. This command can be sent to a selected device or all listener devices. It is
necessary to assign ST2523 as a listener device firstly and then set the trigger mode as bus trigger
mode. Finally send trigger data.
6.2.4
SCPI (Standard Commands for Programmable Instruments)
SCPI is a new general command based on the IEEE488.2-1987 standard. (SCPI is the same as TMSL, a system
language for measurement testers adopted by HP.)
System for Component X
System for Component Y
BUS
Relative information for measurement tester
Common commands and query
Syntax and data structure
Remote control
D C B A A B C D
IEEE488.1 Standard
SCPI SCPI
Where: Level D shows the instrument functions
Level C shows the common system functions
Level B shows the information communication functions
Level A shows the interface functions (IF)
Figure 6-5 SCPI functions levels
