Writes a two-byte little-endian signal at the offset its group defines.
Writes a one-byte signal at the offset its parameter group defines.
Reads a two-byte little-endian signal, or null if it would run past the
payload.
Reads a one-byte signal, or null if the offset is past the payload.
Staticfrom
The eight data bytes of a J1939 frame, addressed by the signals inside them.
A parameter group places each signal at a fixed byte offset, little-endian. A payload starts with every signal marked not available, so a controller writes only the signals it actually reports.