For each ZONE, the user can configure
a firmware update owner CPU and LINK using the FWU_CPU and FWU_LINK fields in the
ZONEx_CFG register. The following restrictions apply when updating code in the Flash
MAIN sectors:
- When in SSUMODE3, the firmware
update owner CPU and LINK defined in the ZONEx_CFG register is the only LINK
allowed to program and erase the Flash MAIN sectors. In addition,
ZONEx_CFG.UPDATE_EN must be set to 0xC to enable updates.
- In SSUMODE1 and SSUMODE2, Flash
write/erase protections are inactive as all ZONES are enabled for full debug. In
these modes, Flash memory can always be programmed or erased. This enables easy
code development.