TriContinent C24000, Руководство по эксплуатации продукта

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OEM communication protocol
C-Series Product Manual
107
OEM communication protocol
OEM communication is a robust protocol that includes automatic recov-
ery from transmission errors. Table 9-3 describes each setting within the
OEM communication protocol.
OEM protocol command block characters
The command block characters in the OEM communication protocol are
described below. All characters outside the command block are ignored.
When developing a parsing algorithm, the programmer should key on
the STX as the beginning of the answer block and the checksum (char-
acter after ETX) as the end of the answer block.
SYNC (FFh)
Used for backward compatibility with older model pumps.
STX (Ctrl B or 02h)
The STX character indicates the beginning of a command string.
Table 9-3: OEM Protocol communication details
Parameter Setting
Character Format
Baud Rate 9600 or 38400
Data Bits 8
Parity None
Stop Bit 1
Command Block
(see "OEM protocol command block characters" for details)
1 SYNC (FFh)
2 STX (Ctrl B or 02h)
3 Pump address
4 Sequence Number/Repeat flag
5+n Data block (length n bytes)
6+n ETX (Ctrl C or 03h)
7+n Checksum
Answer Block
(see "OEM protocol answer block characters" for details)
1 STX (Ctrl B or 02h)
2 Master address (0 or 30h)
3 Status/error code
4+n Data block (length n bytes)
5+n ETX (Ctrl C or 03h)
6+n Checksum