TDK-Lambda Z160-1.3, Руководство пользователя

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9.6.5 Output Queue
The Output Queue is a first-in, first-out (FIFO) data register that stores power supply-to-controller
messages until the controller reads them. Whenever the queue holds one or more bytes, it sets the
MAV bit (4) of the Status Byte register. If too many unread error messages are accumulated in the
queue, a system error message is generated. The Output Queue is cleared at power On and by *CLS.
9.6.6 Error Messages
System Error Messages are read back via the SYST:ERR? query. The error number is the value
placed in the power supply error queue. SYST:ERR? returns the error number into a variable and
combines the number and the error message into a string. Table 9-5 lists the system errors that are
associated with SCPI syntax errors and interface problems. Information within the brackets is not
part of the standard error message, but is included for clarification. When system errors occur, the
Standard Event Status register records them as follows:
Bit Set Error code Error Type Bit Set Error code Error type
5 -100 thru -199 Command 3 -300 thru -399 Device-dependent
4 -200 thru -299 Execution 2 -400 thru -499 Query
Table 9-5: Standard Event Status Register Error Bits
The Status and Error Registers described in the previous section are only one of the status methods
in the IEEE board. There is also a SCPI requirement for error messages that are in the form of:
<Error Number><Comma><Quote><Error Description:Supply Address><Quote>
The user sends the ”SYST:ERR?” query to read the error message. The messages are stored in a
first-in/first-out queue.
The SYST:ERR queue can buffer up to TEN error messages, although the tenth is replaced by the
–350,”Queue Overflow” if an eleventh message is generated. After the queue overflow, only the
first ten messages are stored and the later messages are lost.
The SYST:ERR queue is cleared by:
Reading the messages one at a time using ”SYST:ERR?” until 0,”No error” is read, or
The *CLS (Clear Status) command.
If any message is in the SYST:ERR queue (except ”No error”), then bit 2 of the Status Byte is set. A
Service Request is generated if bit 2 is enabled.