Byte order: little endian
Can be used as extension of the data registers.
For 32-bit data: DWL2 occupies WL2 (low) and WL3 (high)
For 64-bit data: LWL2 occupies WL2 (lowest) and WL3, WL4, WL5 (highest).
FP address: L11A, WL2, DWL4, LWL10
IEC address: %MX7.11.10, %MW7.2, %MD7.4, %ML7.10