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MBR5 User Manual
MBR5 Rev 007
49
and cannot be signaled when the input queue becomes full. Therefore,
characters sent to the MBR5 Meter are lost.
If a new program message is received before the response to a query in a
previous message is read, the output queue is cleared, MAV is set to false, and
the query error bit is set. This error is also referred to as an unterminated error.
Output Queue
Responses to query messages are placed in the output queue. This queue is 128
characters in length. When a response is placed in the output queue, the MAV
bit in the status register is set. The MAV bit is cleared when the response is sent.
Response messages are always terminated with the sequence <LF> and, if the
response is being sent through the GPIB, the EOI signal is set to true when the
last character in a response is sent.
If an attempt is made to read the output queue when it is empty and the
current program message does not contain a query, a query error bit is set.
Error Queue
The error queue is where errors are placed and it can contain up to 10 error
messages. Because it is a FIFO queue, the error returned when the error queue
is read is always the first error that occurred.
If more than 10 errors are put in the error queue, an overflow error occurs and
the last error in the queue is overwritten with error number -‐350 (Queue
Overflow). Each error in the queue consists of an error number and a brief error
message.
Description of Error Numbers
0
No error
No error has occurred.
-‐100
Command error
A command error was detected, but the parser cannot be more specific.
-‐130
Suffix error
An error was detected in the suffix sent with the command, but the parser
cannot be more specific.