Signals

Syntax

signal

 SG_ Name : Start|Size@Order[+|-] (Slope, Offset) [Min|Max] "Units" ReceiverNodes

Signals must adhere to these strict rules of syntax:

Always indented with a single space, immediately preceding SG_
Immediately follow a parent BO_Message , or sibling SG_Signal
No padding with any tabs, blank lines, or other whitespace.

Keywords

Keyword	Type	Description
Name	str	unique mnemonic name for identifying the signal
Start	int	starting bit number for the signal inclusive
Size	int	total length of bits this signal occupies
Order	enum	1 little-endian/Intel · 0 big-endian/Motorola
Sign	enum	+ unsigned integer · – signed integer
Slope	num	multiplied by original signal value · default: 1
Offset	num	added to the original signal value · default: 0
Minimum	num	minimum value relative to Slope and Offset
Maximum	num	maximum value relative to Slope and Offset
Units	[str]	optional units for the return value, such as mph
Receivers	[str]	space-separated BU_Nodes that receive this signal

Example and Dissection

message block

BO_ 420 CruiseControl: 4 SZL SG_ IncSpeedReq : 16|1@0+ (1,0|1] "" XXX SG_ DecSpeedReq : 18|1@0+ (1,0|1] "" XXXCM_ "(* ...DecSpeedReq : 18|1@0+ (1,0) [0|1] "" XXX      bit start ___↑ ↑ ↑    ↑↑    ↑↑    ↑  ↑___ receiver=XXX       bit length ___| |    |     |    |___ no units         big-endian ___|    |     |___ minimum=0           unsigned + _|    |     |_ maximum=1                   slope=1 _|_ offset=0*)";

Examples

Here are some examples of real-world Signals that you might encounter in the field.

Constrained Values

As noted in the keywords section above,