Unbrick CYW20719

[Anonymous]

Hello team,

I believe I have accidentally bricked a CYW20719-powered board. My Computer can see a device on COM11 and 12, but the device won't respond to resets, power cycles, or being put into recovery mode, and whenever I try to flash it, I get this error:

Downloading application...

****Download failed ****

Trying baudrate 115200   Conn: PORT=COM11    BAUDRATE=115200

Trying baudrate 3000000   Conn: PORT=COM11    BAUDRATE=3000000

Downloaded 0 code bytes ( 0.0%) and 0 data bytes ( 0.0%). Verified 0 code bytes ( 0.0%) and 0 data bytes ( 0.0%).   Current state: Terminated with error

Failed to determine baud rate

Download failed. This WICED platform of the SDK only supports download to 207x9B1 devices.

Follow the instructions in the 20719-B1 README.txt for downloading the application.

Before this started happening, I received a strange message about the programmer only writing 6 bytes to some 0x5000xxx address, but I don't have that console log saved. I believe this initial failed download was due to broken solder joints on the USB connector, which has since been fixed.

Additionally, another engineer has told me that the IC clocks are still running.

Is there any way I can repair this board?

Thank you,

Nicholas

[AnjanaM_61]

Hi Nicholas,

1. Could you please confirm whether you are using 20719 Eval board or a custom board?

2. Can you please try connecting the HCI UART with CyBluetool (CyBluetool (Windows Installer) ) and check if the device is giving any response to the HCI commands from Bluetool?

3. Could you please try using a different USB-UART bridge for the HCI UART and try if it works?

Thanks,

Anjana

[AnjanaM_61 · Accepted solution]

Hi Nicholas,

Not sure you tried it out or not.

If the device is working with CyBluetool commands (after connecting the HCI uart pins directly via some other USB UART bridge), then you can confirm the chip is in working condition. Then the problem may be with USB-UART bridge on your board.

If not, mostly the chip might have damaged, I don't think we can recover it back.

Thanks,

Anjana