Ametek 3050-AMS, Руководство пользователя

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Serial Communications | 5-1
SERIAL COMMUNICATIONS
Protocol
The protocol used for the 3050-AMS Moisture Analyzer is a master/slave,
command/response communication with the master initiating all trans-
fers. The message format for transfers initiated by the master is seen in
Figure 5-1.
• All elements of this protocol are sent as ASCII characters.
• The Start Flag is the character ‘>’, $3E.
• The End Flag is a carriage return, $0D.
• The Node address is a two byte hexadecimal ASCII value in the range
$00 through $EF.
• Addresses $F0 through $FF are reserved.
• The command byte is a single ASCII character.
• The Data field is of variable length and contains ASCII characters.
• The checksum is a two byte ASCII hexadecimal field representing the
modulo 256 sum of Node Address, Command Byte, and Data fields
(excludes the start flag).
• A master can issue a wildcard in lieu of a checksum.
Figure 5-1.
Message format for
transfers initiated by
the master.
Node Address
Data
Check Sum
End Flag
Command Byte
Start Flag