AN3154 datasheet(21/34 Pages) STMICROELECTRONICS

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AN3154

Bootloader command set

Note:

When writing to the RAM, you should take care not to overlap the first RAM memory used by

the bootloader firmware.

No error is returned when performing write operations on write protected sectors.

Figure 16. Write Memory command: host side

Note:

If the start address is invalid, the command is NACKed by the device.

The host sends the messages as follows:

Command message: Std ID = 0x31, DLC = 0x05, data[0] = 0xXX: MSB address,..., data[3] =

0xYY: LSB address, data[4] = N-1 (number of bytes to be written - 1), 0 < N

≤255).

then the host send N/8 message

Data message: Std ID = 0x31, DLC_1 = to 8, data = byte_11, … byte_18…

Data message_M: Std ID = 0x04, DLC_M = 1 to 8, data = byte_m1, …, byte_M8

Note:

DLC_1 + DLC_2 + ... DLC_M = 256 maximum

After each message the host receives the ACK or NACK message from the device

The bootloader does not check the standard ID of the data, so any ID from 0h to 0xFF can

be used. It is recommended to use 0x04.

AN3154 Datenblatt(PDF) 21 Page - STMicroelectronics