Can be used as an address or constant modifier (e.g. IXWX100 on 16-bit PLCs, DIXY300 or DIXS1:DIYUM10 on 32-bit PLCs).
FP address: IX, IY, I2, IA, DIX, DIY, DI2, DIA
IEC address: %MW6.0, %MW6.1, %MW6.2, %MW6.10, %MD6.0, %MD6.1, %MD6.2, %MD6.10