SYSTem:ALARm?

Syntax | Description | Parameters | Remarks | Return Format | Example

Syntax

SYSTem:ALARm?

Description

This command reads the alarm data from the alarm queue (one message is read and deleted from the queue each time this command is executed). A record of up to 20 alarms can be stored in the instrument's alarm queue.  

Used With:

• 34921A through 34925A Multiplexer Modules

• 34950A Digital I/O Module (digital input and counter channels only)

• 34952A Multifunction Module (digital input and totalizer channels only)

Remarks

• Each time you start a new scan, the instrument clears all readings (and the alarm queue) stored in reading memory from the previous scan. Therefore, the contents of memory are always from the most recent scan.

• Alarm data is retrieved in first-in-first-out (FIFO) order. The first alarm returned is the first alarm that was stored.

• Up to 20 alarms can be logged in the alarm queue. If more than 20 alarms are generated, they will be lost (only the first 20 alarms are saved).

• To retrieve scanned readings and alarm data from reading memory without clearing the information, use the FETCh? command.

• The alarm queue is cleared by the *CLS (clear status) command, when power is cycled, and by reading all of the entries. A Factory Reset (*RST command) or Instrument Preset (SYSTem:PRESet command) does not clear the alarm queue.  

Return Format

One string is returned each time this command is executed. The command reads the alarm data and clears one alarm event from the alarm queue. If readings are acquired using the internal DMM independently (without a multiplexer scan), the channel number will be logged as channel "0".

The command returns a string in the form shown below (independent of FORMat:READing commands):

Example

The following command reads one message from the alarm queue and removes that message from the queue.

SYST:ALAR?

Typical Response:  -1.17616000E-04 VDC,2004,11,21,15,54,50.184,1003,1,3