23.5 Implementation Considerations
In AHB mode, the user may perform byte, half word and word accesses from the fabric to MSS. However, in APB16 mode, the user can only cause a word access to occur to an MSS slave. This is done by two accesses over the APB16, one of which is to write a 16-bit holding register (in the case of writes) or to read a 16-bit holding register in the case of reads.