RoadRunners – Communication Protocol
TF -
Protocol of communication
26/46
January 2007
3/ Type
The Type field defines the type of command to be sent to the reader, it is 1 byte long.
Type
Description
A
Get config
: asks the reader to give the configuration options for the selected
symbology. (1) (*)
B
Set config
: sets an options configuration for the selected symbology. (1)
C
Set Default:
sets the default options configuration for the selected
symbology(ies).
D
Usual Command.
E
Special Command
(with parameters). (2)
(*): This Type of command is not available with "A" header.
(1): This command concerns the whole set of options available for one symbology. Its
description will be given in the section "Command field".
(2): This type is used for commands requiring non Boolean information. Their length will be
at least 2 bytes, the first one defining the type of command, the other(s) being the
parameter(s) to use. More details will be given in the section "Command field".
All the commands will answer “0” if the frame is wrong.
Commands with type B, C, D or E will answer “1” as an acknowledgment of good reception
of the command.
The “Get config” command (type A) will answer 2 or 4 bytes : the two firsts follow the
format described below (see “set config” command field). The third and fourth bytes
correspond to minimum and maximum lengths if the selected symbology supports this option.
4/ Size
This field specifies the length (bytes) of the following field (commands). It will be set to "0"
if the type was "A" (Get Config) or "C" (Set Defaults),