The configured address in the QUADSPI_AR is divided by 2 (shifted right by 1bit) in DUAL bank mechanism, because each connected memory represents the half of the total size set in the FSIZE field. That’s why when writing data at a specific address, the QSPI peripheral outputs the half of the SW configured address.
The LSB bit of address represents specific flash:
- even addresses are stored in Flash 1
- odd addresses are stored in Flash 2
You can see write operations to addresses 0x20 and 0x21 in the picture.