AT89C5132-ROTIL datasheet(19/33 Pages) ATMEL

19 / 33 page

4256B–USB–03/06

AT89C5132

Figure 5. Example of Firmware Download Zero Length DFU_DNLOAD Request

The Host sends a DFU_DNLOAD request with the wLength field cleared to 0 to the device to

indicate that it has completed transferring the firmware image file. This is the final payload

packet of a download operation.

This operation should be preceded by a Long Jump address specification using the correspond-

ing Flash command.

Answers from

Bootloader

After each program request, the Host can request the device state and status by sending a

DFU_GETSTATUS message.

If the device status indicates an error, the host can send a DFU_CLRSTATUS request to the

device.

Reading the Flash

The flow described below allows the user to read data in the Flash memory. A blank check com-

mand on the Flash memory is possible with this flow.

This operation is performed in 2 steps:

DFU_DNLOAD request with the read command (6 bytes)

DFU_UPLOAD request which correspond to the immediate previous command.

First Request from Host

The Host sends a DFU Download request with a Display command in the data field.

OUT

Prog_Start + (EP0 FIFO length - 6) x 00h

SETUP

DFU_DNLOAD

OUT

X offset bytes + Firmware Packet 1

OUT

Firmware Packet 2

OUT

Firmware Packet n + DFU suffix

ZLP

OUT

Display_Data (6 bytes)

SETUP

DFU_DNLOAD

ZLP

AT89C5132-ROTIL Datasheet(PDF) 19 Page - ATMEL Corporation