Dfu Bootloader Commands; Dfu_Upload Request Commands; Read Memory; Table 6. Summary Of Dfu Class-Specific Requests - ST STM32F105 Series Application Note

AN2662
Note: The Detach request is not meaningful in the case of the bootloader. The bootloader is
started by a system reset depending on the boot mode configuration settings, which means
that no other application is running at this time.
Table 6.
bmRequest
00100001b
00100001b
10100001b
00100001b
00100001b
00100001b
00100001b
Communication safety
The communication between Host and Device is secured by the embedded USB protection
mechanisms (CRC checking, Acknowledgements ...). No further protection is performed for
transferred data or for bootloader specific commands/data.
4.3

DFU bootloader commands

The DFU_DNLOAD and DFU_UPLOAD requests are mainly used to perform simple Write
Memory and Read Memory operations. They are also used to initiate the integrated
bootloader commands (write, read unprotect, erase, set address ...). The
command then triggers the command execution.
The selection of a command through the DFU download request is done through the
parameter in the USB request structure. If wValue = 0 then the data sent by the Host after the request
is a bootloader command code. The first byte is the command code and the other bytes (if any) are the
data related to this command.
The selection of a command through the DFU upload request is done through the
parameter in the USB request structure. If wValue = 0 then Get Command is selected and performed.
4.4

DFU_UPLOAD request commands

The upload request allows different commands to be performed. The command selection is
done through the value of
described in
4.4.1

Read memory

The Read operation is selected when
Summary of DFU Class-Specific requests
bRequest
DFU_DETACH
DFU_DNLOAD
DFU_UPLOAD
DFU_GETSTATUS
DFU_CLRSTATUS
DFU_GETSTATE
DFU_ABORT
parameter wValue in the USB request structure. The operations
Section 4.4.1 to Section 4.5.5
Doc ID 14156 Rev 1
wValue wIndex
wTimeout Interface
wBlockNum Interface
Zero Interface
Zero Interface
Zero Interface
Zero Interface
Zero Interface
are supported.
> 1.
wValue
DFU bootloader
wLength Data
Zero None
Length Firmware
Length Firmware
6 Status
Zero None
1 State
Zero None
DFU_GETSTATUS
wValue
wValue
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