The pre-calculated checksum must be present in the last location of the section
to be checked. If the BOOT section is to be checked, the checksum must be saved in the last
bytes of the BOOT section. The same is done for APPLICATION and the entire Flash. Table 1 shows explicitly how the checksum must be stored for the different sections. Refer to
the CRCSCAN.CTRLB register description for how to configure the sections to be checked.
Table 1. Placement of the Pre-Calculated
Checksum for CRC16 in Flash
| Section to Check |
CHECKSUM[15:8] |
CHECKSUM[7:0] |
| BOOT |
BOOTEND-1 |
BOOTEND |
| BOOT and APPLICATION |
APPEND-1 |
APPEND |
| Full Flash |
FLASHEND-1 |
FLASHEND |
Table 2. Placement of the Pre-Calculated
Checksum for CRC32 in Flash
| Section to Check |
CHECKSUM[31:24] |
CHECKSUM[23:16] |
CHECKSUM[15:8] |
CHECKSUM[7:0] |
| BOOT |
BOOTEND |
BOOTEND-1 |
BOOTEND-2 |
BOOTEND-3 |
| BOOT and APPLICATION |
APPEND |
APPEND-1 |
APPEND-2 |
APPEND-3 |
| Full Flash |
FLASHEND |
FLASHEND-1 |
FLASHEND-2 |
FLASHEND-3 |