at89c5131a ATMEL Corporation, at89c5131a Datasheet - Page 20

• Manufacturer Part Number: at89c5131a
• Description: Usb Microcontrollers
• Manufacturer: ATMEL Corporation

Answers from the Device to a
Blank Check Command
Programming
Configuration
Information
Request from Host
Answers From Bootloader
20
AT89C5131A USB Bootloader
The Host controller send a GET_STATUS request to the device. Once internal blank
check has been completed, the device sends its status.
•
•
The flow described below allows the user to program Configuration Information regard-
ing the bootloader functionality.
•
Take care 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 command in the data field (6 bytes).
The device has two possible answers to a DFU_GETSTATUS request:
•
•
Id_write_command
If the device status is “OK”:
the device memory is then blank and the device waits the next Host request.
If the device status is “errCHECK_ERASED”:
the device memory is not blank. The device waits for an DFU_UPLOAD request to
send the first address where the byte is not 0xFF.
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“.
Command
Identifier
04h
BSB
SBV
P1_CF, P3_CF and P4_CF
Fuse bits (BLJB, X2 and OSCON bits) (see section “Mapping and Default
Value of Hardware Security Byte”)
SETUP
OUT
IN
data[0]
01h
02h
data[1]
00h
01h
02h
03h
04h
05h
06h
00h
data[2]
Value
Value
Write_command (6 bytes)
DFU_DNLOAD
ZLP
data[3]
data[4]
Write value in BSB
Write value in SBV
Write P1_CF
Write P3_CF
Write P4_CF
Write value in SSB
Write value in EB
Write value in Fuse
(HSB)
Description
4287C–USB–11/04