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WICED Smart Bluetooth

New Contributor II

My company is currently having an issues with quite a few of our devices that use the BCM20736s BLE controller. The controller on each device was programmed one time successfully. After we discovered that the radios were not communicating, wireless or UART via traces, we attempted to reprogram the controller and failed.

These devices were programmed via the WICED IDE. The make target used was mistakenly for the 20737 platform instead of the 20736 platform. The crystal warm up time of the 20737 platform was left at the default value of 2800.

I have attempted to recover the radios using the following procedure with no success:

Power off the device

Short SDA to GND

Connect the HCI UART to the PC

Power up the device

Reset the controller for ~3s

Disconnect SDA from GND

Attempt to program by replacing 'download' with 'recover' in the make target. (I've also tried using Chipload.exe using -nodlminidriver)

All of these devices appear to function when made with the 20736 platform with the crystal warm up time set to 5000.

Is there anyway I may be able to salvage these chips?

1 Solution

The key point here was to disable the eeprom so that the controller can boot from its ROM. You may

tweak a little by doing the following:

1) short the SDA to ground

2) power up and wait 3s

3) remove the short

4) hooked up HCI connection and perform recovery

As to the termination during the DL process, that's another story...

Can you provide the download log with VERBOSE=1 turn on?

Just so we are on the right page, are you doing all these using the FTDI cable connected directly between your

product board and PC, without the tag3 board anywhere?

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