Data will be transferred serially according to RS232 protocol
using the following settings.
Female DB9DCE pin numbering and definitions: recommended
communication rates are: (higher baud rates are fine but 9600 is
by far the most common and is su
ffi
cient for the volume of data
being transmitted)
3-6-3 Data structure
Note
•
All numbers shown are in the protocol description are in
string unless indicated otherwise. Percentages are shown in
decimal.
General Command Form
•
STX. The first character is the standard Start of Text (STX)
character ‘S’.
•
Address. The second character is the device address. If a device
does not support addressing, these should be 0 and 9 to act as
the global address.
•
Type. The third character is the command type. There are four
types of commands:
o Command0
o Ack1
o Nak2 (option)
o Notification 3 (option)
•
Property ID. The four and fifth and characters are the property
identifier. By using one byte we have 256
•
Data Length. The sixth character is the number of characters in
the parameter data section.
•
Data. Following the sixth character is the parameter data section
that is as many characters long as the sixth character indicates. If
the sixth character is 00 (as with the Reset command for
example) then there are no characters in the parameter section.
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