DocID017063 Rev 5

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AN3154

Bootloader command set

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Note:

1

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

the bootloader firmware.

2

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:

1

DLC_1 + DLC_2 + ... DLC_M = 256 maximum

2

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

3

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.