6. LW3 Programmers’ Reference
HDMI20-OPTC series – User's Manual
39
6.1.2.
Escaping
Property values and method parameters can contain characters that are used as control characters in the
protocol. They must be escaped. The escape character is the backslash (‘\’) and escaping means injecting
a backslash before the character that should be escaped (like in C language).
Control characters are the followings: \ { } # % ( ) \r \n \t
Example:
The original text: John
●
(Doe).
●
#3:
●
5%2=1
●
node1\node11
The escaped text: John
●
\(Doe\).
●
\#3:
●
5\%2=1
●
node1\\node11
6.1.3.
Error Messages
There are several error messages defined in the LW3 protocol, all of them have a unique error number.
Format
: XE
●
[primitive]
●
%EYYY:
●
[Error message]
Legend:
‘X’ can be:
‘-’:
syntax error. Cannot parse the command at all.
‘n’:
node error.
‘p’:
property error.
‘m’:
method error.
YYY: error code, which can be one of the followings:
Error code
Name
Default text
000
Lw3ErrorCodes_None
001
Lw3ErrorCodes_Syntax
Syntax error
002
Lw3ErrorCodes_NotFound
Not found
003
Lw3ErrorCodes_AlreadyExists
Already exists
004
Lw3ErrorCodes_InvalidValue
Invalid value
005
Lw3ErrorCodes_IllegalParamCount
Illegal parameter count
006
Lw3ErrorCodes_IllegalOperation
Illegal operation
007
Lw3ErrorCodes_AccessDenied
Access denied
008
Lw3ErrorCodes_Timeout
Timeout
009
Lw3ErrorCodes_CommandTooLong
Command too long
010
Lw3ErrorCodes_InternalError
Internal error
011
Lw3ErrorCodes_NotImplemented
Not implemented
012
Lw3ErrorCodes_Node_Disabled
Node disabled or standby mode active
6.1.4. Prefix Summary
The following prefixes are defined in the LW3 protocol:
‘n-’:
a node,
‘nE’:
an error for a node,
‘nm’:
a manual for a node,
‘pr’:
a read-only property,
‘pw’:
read-write property,
‘pE’:
an error for the property,
‘pm’:
a manual for the property,
‘m-’:
a method,
‘mO’:
a response to a success method execution,
‘mF’:
a response to a failed method execution,
‘mE’:
an error for a method,
‘mm’: a manual for a method.
6.2.
The Tree Structure
The /MEDIA node is used by the LDC to connect input ports
to output ports on different layers. Each subnode of /MEDIA
is representing a layer, e.g. video (/MEDIA/ VIDEO), RS-232 (/
MEDIA/ UART) or Ethernet(/MEDIA/ ETHERNET). Each layer
has a crosspoint to define connections between the ports
associated with the layer, all of them are represented by a
specific node. E.g. the video layer node is /MEDIA/VIDEO:
under the video layer node, the video crosspoint node (XP) and
the video ports (I1, O1, …) are located. The /SYS node is used
for system-related settings such as front panel settings and
health status parameters. The /MANAGEMENT node contains
network-related parameters, date-time settings, and version
numbers. The /EDID node contains all EDID-related settings
such as factory pre-programmed EDIDs and User EDIDs. All
input and output port settings, crosspoint state, etc... are under
the /MEDIA node.
INFO: The tree structure is available in
the of LDC.
MANAGEMENT
MEDIA
EDID
SYS
/
ETHERNET
UART
VIDEO
PRESETS
REMOTE
EVENTS
