TUSB3410_10 Datasheet, PDF (79/98 Pages) Texas Instruments – USB to Serial Port Controller

TUSB3410 Bootcode Flow
OFFSET
0x0000
0x0001
0x0002
0x0003
0x0004
0x0005
0x0006
0x456d
Table 11−7. Autoexec Binary Firmware
TYPE
SIZE VALUE
DESCRIPTION
Signature0
1
0x10 FUNCTION_PID_L
Signature1
1
0x34 FUNCTION_PID_H
Data Type
1
0x07 Autoexec binary firmware
Data Size (low byte)
1
0x67 0x4567 bytes of application code
Data Size (high byte)
1
0x45
Check Sum
1
0xNN Checksum of the following firmware
Program
0x4567
Binary application code
Data Type
1
0x00 End of header
11.7 USB Host Driver Downloading Header Format
If firmware downloading from the USB host driver is desired, then the USB host driver must follow the format
in Table 11−8. The Texas Instruments bootloader driver generates the proper format. Therefore, users only
need to provide the binary image of the application firmware for the Bootloader. If the checksum is wrong, then
the bootcode disconnects from the USB and waits before it reconnects to the USB.
Table 11−8. Host Driver Downloading Format
OFFSET
TYPE
SIZE VALUE
DESCRIPTION
0x0000 Firmware size (low byte)
1
0xXX Application firmware size
0x0001 Firmware size (low byte)
1
0xYY
0x0002 Checksum
1
0xZZ Checksum of binary application code
0x0003 Program
0xYYXX
Binary application code
11.8 Built-In Vendor Specific USB Requests
The bootcode supports several vendor specific USB requests. These requests are primarily for internal testing
only. These functions should not be used in normal operation.
11.8.1 Reboot
The reboot command forces the bootcode to execute.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_OUT
bRequest
BTC_REBOOT
wValue
None
wIndex
None
wLength
None
Data
None
01000000b
0x85
0x0000
0x0000
0x0000
11.8.2 Force Execute Firmware
The force execute firmware command requests the bootcode to execute the downloaded firmware
unconditionally.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_OUT
01000000b
bRequest
BTC_FORCE_EXECUTE_FIRMWARE
0x8F
wValue
None
0x0000
wIndex
None
0x0000
wLength
None
0x0000
Data
None
72 TUSB3410, TUSB3410I
SLLS519H—January 2010