HP 8167A, Руководство пользователя, Страница: 68 / 262

4
3. An EOI (End Or Identify) sent with any character is put into the input queue
as the character followed by a line feed (LF , 0A
16
). If EOI is sent with a LF ,
only one LF is put into the input queue .
4. The parser starts if the LF character is received or if the input queue is full.
Clearing the Input Queue
Switching the power o, or sending a Device Interface Clear signal, causes
commands that are in the input queue , but have not been executed to be lost.
The Output Queue
The output queue contains responses to query messages . The tunable laser
source transmits any data from the output queue when a controller addresses
the instrument as a talker .
Each response message ends with a carriage return (CR, 0D
16
) and a LF (0A
16
),
with EOI=TRUE. If no query is received, or if the query has an error , the
output queue remains empty .
The Message A vailable bit (MA V , bit 4) is set in the Status Byte register
whenever there is data in the output queue .
The Error Queue
The error queue is 30 errors long. It is a FIFO queue (rst-in rst-out). That is ,
the rst error read is the oldest error to have occurred. A new error is only put
into the queue if it is not already in it.
If more than 29 errors are put into the queue , the message '-350 <Queue
Overow>' is placed as the last message in the queue .
4-4 Remote Operation