B&B Electronics 232OPSDA manual Syntax

Table 3.2 - Equivalent Values

ASCII	Decimal	Hexadecimal
!	33	21h
#	35	23h
0	48	30h
A	65	41h
D	68	44h
O	79	4Fh
R	82	52h
S	83	53h
NUL	0	0h
SOH	1	1h
STX	2	2h
ETX	3	3h
EOT	4	4h
ENQ	5	5h
ACK	6	6h
BEL	7	7h

Syntax

As mentioned earlier, the command string consists of four bytes. The first byte is the start of message byte. The start of message byte is always the “!” character. The second byte is the address byte. This byte allows each unit to have a unique address (useful in RS-

485networks). Since the 232OPSDA uses RS-232 communications, this byte is the ASCII “0” (zero) character and cannot be changed. The next two bytes are the command characters. These bytes are used to specify which command will be executed by the module. Some commands require a fifth byte, a data byte.

Command Syntax: ! 0 _ _ _

Data Byte

2nd command Byte 1st Command Byte Address Byte Start of Message Byte

12Documentation Number 232OPSDA1397 Manual

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