Addressing the Flash

The data space uses byte accessing but since the Flash sections are accessed as words and organized in pages, the byte-address of the data space must be converted to the word-address of the Flash section.

The most significant bits of the data space address select the NVM Lock bits or the Flash section mapped to the data memory. The word address within a page (WADDR) is held by bits [WADDRMSB:1], and the page address (PADDR) by bits [PADDRMSB:WADDRMSB+1]. Together, PADDR and WADDR form the absolute address of a word in the Flash section.

The least significant bit of the Flash section address is used to select the low or high byte of the word.

Figure 1. Addressing the Flash Memory