AT89C51SND1_06 ATMEL [ATMEL Corporation], AT89C51SND1_06 Datasheet - Page 21

• Manufacturer Part Number: AT89C51SND1_06
• Description: USB Microcontrollers
• Manufacturer: ATMEL [ATMEL Corporation]

Programming
Configuration
Information
Request from Host
Answers from
Bootloader
4254C–MP3–03/06
The flow described below allows the user to program Configuration Information regarding the
bootloader functionality.
•
Ensure that the Program Fuse bit command programs the 4 Fuse bits at the same time.
To start the programming operation, the Host sends DFU_DNLOAD request with the Write com-
mand in the data field (6 bytes).
The device has two possible answers to a DFU_GETSTATUS request:
•
•
Command Identifier
Id_write_command
Boot Process Configuration:
–
–
–
If the chip is protected from program access, a “err_WRITE” status is returned to the Host.
Otherwise, the device status is “OK“.
BSB
SBV
Fuse bits (BLJB, X2B) (see Section “Mapping and Default Value of Hardware Security
Byte”, page 3).
04h
data[0]
01h
02h
SETUP
OUT
IN
data[1]
00h
01h
05h
06h
00h
data[2]
Value
Value
Write_command (6 bytes)
DFU_DNLOAD
ZLP
data[3]
data[4]
AT89C51SND1
Write value in BSB
Write value in SBV
Write value in SSB
Write value in EB
Write value in Fuse (HSB)
Description
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