How to disable SA4 sector protection in MB91F469G?

[ryko_3280246]

Hello,

I'm using MB91F469B mcu and I want to disable SA4 sector (0x00248000) protection to erase this sector and change BSV1 and BSV2 vectors values.

How can I do what?

[Praveen · Accepted solution]

If BSV1/BSV2 have a valid vector (0x40000..0x24FFFF) internal bootloader (serial Flash Programming mode via UART interface) cannot be entered during BootRom execution after reset.

In that case the device can only be handled within a Parallel Flash Programming environment.

In case SA4 Flash sector is write protected, SA4 cannot be erased separately but by a full chip erase.

However, BSV1/BSV2 in sector SA5 can be invalidated in case SA5 is not write protected. BSV1 must be overwritten with value 0x00000000. This allows to get connection via Serial Flash Programmer during BootRom execution and single sectors can be erased in case they are not write protected.