In the memory map (Figure 2, page 45, RM0091 Rev 6), a region of memory is depicted at 0x50000000 - 0x50001fff; this region is labeled IOPORT. However, I could not find any other reference to that in the entire Reference Manual for the STM32F0x1/STM32F0x2/STM32F0x8 Cortex-M0 microcontrollers. Did a quick search here (no hits) and Google, and nothing. So, does anyone know what that refers to? Is it of any use?