API Commands Appendix A
A-56 ChartScan User’s Manual
U - User Status
TYPE
System
EXECUTION
Immediate
SYNTAX
Ureq
Request information about various internal conditions of the unit where req
refers to one of the following request types:
0 - Query and clear the Event Status Register (ESR)
1 - Query the Status Byte Register (STB)
2 - Query and clear Calibration Status Register (CSR)
3 - Query system settings
4 - Query current High/Low/Last registers
5 - Query and clear current High/Low/Last
6 - Query the Buffer Status String
7 - Query assigned alarm outputs
8 - Query configured channels
9 - Query digital inputs
10 - Query memory option (in Kbytes)
11 - Query all channels having programmed valid alarm setpoints
12 - Query last calibration time/date
13 - Query last scan read
14 - Query card IDs
15 - Query product information
16 - Query measuring mode parameters
17 - Query root mean square (RMS)
18 - Query acquisition states and various system flags
DESCRIPTION
The User Status (U) command is used to return information about various conditions of the unit , and may be sent
at any time without interfering with normal operation. Any error conditions, except Calibration Errors, are cleared
after the status string is read by the controller. Calibration errors are cleared when the unit is calibrated.
Status strings are returned when the unit is next addressed to Talk. The terminators used and the use of the End
Or Identify (EOI) line can be changed with the Set Query Terminator (Q) and Set User Terminator (V) commands.
If the unit is configured to trigger on Talk, requesting a status report will not cause the unit to trigger.
The following paragraphs provide more detailed information about the U responses.
U0: Reads and clears the Event Status Register (ESR). Refer to the Status and Event Reporting sections of
Appendix C for details on status reporting. U0 responds with:
001 - Acquisition Complete
016 - Execution Error
002 - Stop Event
032 - Command Error
004 - Query Error
064 - Buffer 75% Full
008 - Device Dependent Error
128 - Power-On
U1: Reads the Status Byte register (STB). The response to this request is the same as in an IEEE 488 Serial
Poll except that bit 6 carries the Master Summary Status (MSS) rather than the Request for Service. The Status
Byte register is a read-only register whose bits correspond to those of the Service Request Enable (SRE) register
with the addition of bit value 64 which responds with the Master Summary Status. The Master Summary Status
bit indicates whether or not this device needs service. It responds with:
001 - Alarm
016 - Message Available
002 - Triggered
032 - Event Detected
004 - Ready
128 - Buffer Overrun
008 - Scan Available
U2: Read and clear the Calibration Status Register (CSR). The response to this request is the current contents
of the Calibration Status Register. This register contains information regarding the calibrati on of the unit and any
errors encountered while attempting to calibrate the unit. Refer to the following figure for details about the
Calibration Status Register.