Bootloader command set

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DocID017063 Rev 5

Figure 25. Readout Protect command: device side

1. RDP_PRM = Readout Protect

The STM32 sends messages as follows:

ACK message: Std ID = 0x82, DLC = 1, data[0] = ACK if the content of the command is

correct and ROP is not active else data[0] = NACK.

3.12

Readout Unprotect command

The Readout Unprotect command is used to disable the Flash memory read protection.

When the bootloader receives the Readout Unprotect command, it transmits the ACK

message to the host. After the transmission of the ACK message, the bootloader erases all

the Flash memory sectors and it disables the read protection for the entire Flash memory. If

the erase operation is successful, the bootloader deactivates the RDP.

At the end of the Readout Unprotect command, the bootloader transmits an ACK message

and generates a system Reset to take into account the new configuration of the option

bytes.