LAUNCHXL-CC2640R2: Bricked CC2640 chip

Hi Experts,

Good day! Please help us with the customer's concern below.

Here is the full details of inquiry:

I have a Launchpad LaunchXL CC2640R2 Development Board and have "bricked" the chip by mistakenly uploading an *.elf file instead of Hex and overwritten the CCFG bitfields. I can no longer access the chip. I have spent a couple of days reading the forums and it seems many others have had this issue as well. Here is what I have tried:

1. Try mass erase using the Uniflash tool in Ubuntu that I have been using. Says it massed erase successfully, but then I can't program or debug .. I get an error: "Status: IcePick_C: Error connecting to the target: (Error -241 @ 0x0) A router subpath could not be accessed. A security error has probably occurred."

2. Try mass erase using Windows & Flash programmer 2. It will say it mass erases, but still I get an error: when I try to upload a new file or debug.

3. Attached external debugger directly bypassing on-board XDS110 interface. Try to connect using openOCD. Same issue, can't connect to chip - says DAP interface is not available.

4. Try openOCD through the on-board XDS110 interface. Can definitely talk to XDS110 but can't access JTAG interface on CC2640R2.  

5. Try a different computer and USB cable. Same issues.

6. I even found a guy on the web that built a cool tool  https://github.com/firmwaremodules/iotfirmware/tree/master/tools to try to recover a bricked board by accessing a part of the CCFG fields that may still be accessible. I downloaded and ran this on a windows machine. But still the same issue.

At this point, I believe I have mistakenly overwritten all of the CCFG fields - and most importantly the JTAG fields - meaning I can't access the CC2640R2 chip & have bricked the board. Most of the forum threads end with "I suggest you to ask for help from www.ti.com", so that's what I am doing. 

Best regards,

Jonathan