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MessengerBLE
User Guide
9.20
J1939 SPN Configuration – Type 14
Within a PGN message received on the CAN bus are encoded many values. These
values are referred to as SPNs. When a PGN message is received, it is decoded by the
configuration shown below. The decoded value is stored in the corresponding SPN data
register. There are several common SPNs that are pre-defined in the system. The user
can also define a different or proprietary SPN for their own application. The maximum
number of SPNs supported is 150.
Parameters for SPN Configuration
Parameter
Code
Reference Description
Default
1
Name
A representative name to reference the
SPN by.
C
ASCII Text
30 characters max
2
Enable
Is this SPN enabled for decoding from a
received PGN.
0 = no
1 = yes
3
Number
Unique number defined by the SAE.
4
Type
The value decoded from the PGN
message will be of this type.
8
0 = none
1 = digital (2-bits, no scaling)
2 = numeric (a numeric value only, no
scaling)
3 = analog (requires scaling)
4 = text (treat as string value)
5 = other
5
Start Bit
Defines the start bit of the SPN value in
the 64-bit J1939 payload.
8
Range: 0-63
6
Number
of Bits
Defines the number of bits in the SPN
value, starting with the start bit.
8
Range: 0-64
7
Multiplier The default multiplier will be per the
J1939 SAE docs but can be changed by
the user.
8
float
8
Multiplier The default multiplier will be per the
J1939 SAE docs but can be changed by
the user.
8
