Some problems about DFU via UART

[DonWoo]

Hello,

A problem occurs when i run the DFU over UART on my board.My bootloader project references to nRF51_SDK_9.0.0_2e23562\examples\dfu\bootloader\pca10028\dual_bank_serial_s110

Here is my steps:

1、Configure TX、RX pins;Modify the UART mode to FLOW_CONTROL_DISABLED;Now I can send and receive datas；

2、Erase my board ,then download the SOFTDEVICE from nRF51_SDK_9.0.0_2e23562\components\softdevice\s110\hex；

3、Compile my bootloader project then download.

4、Download the app hex file；

when I download the app hex file，here comes the problem.

Then I try to catch the data ,and found I can sent the ack of the start packet,but the ack of the first block of Application image is missing,and it turns into another invalid ack :0XFC.

Now I do not know how to solve this problem.Can anyone help me?

Regards, DW.

[bjorn-spockeli]

There are some timing considerations that must be taken in to account on the host side when using the serial bootloader. I suggest that you take a look at this python script from pc-nrfutil, which is used to perform serial DFU. Around line 60 you'll see several the definitions of several delays, e.g. how long you should wait before sending more data over the UART after you have sent the start packet.

Best regards

Bjørn

[coolnumber9]

@bjorn-spockeli : I tried to edit the python script (class DfuTransportSerial in dfu_transport_serial.py):

DEFAULT_SERIAL_PORT_TIMEOUT = 5.0 #(Original is 1.0)
ACK_PACKET_TIMEOUT = 5.0 #(Original is 1.0)
SEND_INIT_PACKET_WAIT_TIME = 5.0  #(Original is 1.0)
SEND_START_DFU_WAIT_TIME = 15.0 #(Original is 10.0)

Adjusted the timeouts but still the same problem after nrfutil sends the application firmware file (512 KB). "Failed to upgrade target. Error is: No data received on serial port. Not able to proceed."

[coolnumber9]

@donwoo, @bjorn-spockeli : Here are my screenshots...

DFU Serial on command line

UART Sniffed Data

[bjorn-spockeli]

@coolnumber9: Are you using one of the serial bootloaders from SDK v11.0.0 ?

[coolnumber9]

@bjorn-spockeli :

• When the pre-built serial bootloader hex from SDK v11.0.0 are used, no problem encountered. The device was programmed successfully.
• Then, i modified the serial bootloader example for our specific need. Rebuilt the hex file and loaded it on the nRF52 (PCA10040) devkit. This is when the problem happened shown in the screenshots in my previous comment.

[coolnumber9]

@bjorn-spockeli: Let me know if I should be posting my problem as a different question. Thanks!