NF ZM2371, Инструкция по эксплуатации

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5.1 Preparations Before Use
5-12 ZM2371/ZM2372
5.1.5 Precautions on Communication

Input buffer
•
The sent commands are stored in the input buffer once, and they are interpreted and
executed in order.
The input buffer capacity is 1K bytes (K=1024). Even program messages exceeding this
size are all interpreted and executed in order.
•
If a command out of the specification is found during interpretation or execution, an error
occurs and after that, the command is not executed until the program message terminator
is reached.

Output buffer
•
The output buffer capacity is 64K bytes (K=1024).
•
If exceeding the maximum capacitance, the output buffer is cleared and the query error
bit of standard event status register is set to “1”. After that, the command interpretation
and execution are performed as usual, but the response messages generated until the
program message terminator is reached are all dumped.

Error queuing
•
The number of error messages that can be retained is maximum 16.
•
If exceeding this capacity, 16th error message changes to “Queue overflow” indicating that
the error queue overflows. Error messages after that are dumped. Error messages up to
15th message are retained.

Program message terminator
When a command is sent from the controller, add LF (Line Feed, 0A hex) at the end of
transmitted character string as a program message terminator. Also, add EOI (END
message) to the last byte. Sending a command without adding LF or EOI causes a
malfunction in some devices.
The program message terminator may not be output unless the program message terminator
is specified in addition to the command body, depending on the driver software used in the
computer for control. Though a new line (NL) may be expressed in place of line feed (LF), the
binary code is same.
The RS-232 does not have the concept of END message and therefore it does not need EOI to
be added.