BCM20737S recovery problems

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Anonymous
Not applicable

Hi

We have made our custom board with BCM20737S. I've difficult to download firmware (via WICED IDE) and recover firmware.

Download never works (i already created a specific discussion for that) and recovery time to time.

As soon i downloaded firmware in recovery mode, parts always boots correctly.

download log is mentionning :

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 execute HCI Reset

sequence to enter in recovery :

     - unplugging everything

     - reset + boot (short to SDA) push

     - powering up chip (USB powered) and connecting uart to PC

     - reset release (boot still pushed)

     - release boot

it works time to time.

WICED IDE make target : WICED_SENSE-BCM920737TAG_Q32 recover UART=COM2

Uart is the right port.

do you know what is this message : Failed to execute HCI Reset ?

do you know if this download impossibility / recovery difficulty can be caused by windows drivers ? (i'm using CYPRESS usb to uart bridge)


thanks a lot

Best regards

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1 Solution
4 Replies
Anonymous
Not applicable

Hello E L,

Our SDK is compatible with the FTDI and Silicon Labs UART devices.

Below is the use of the CP210x Bridge.

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We do not have support for the Cypress Bridge chip.

Thanks,

JT.

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Anonymous
Not applicable

Hi J.t

ok but what is so different between Cypress and the others ?

My chip is well enumerated as virtual COM port and time to time i can recovery my board without any errors.

as soon it is enumerated in windows, normally it becomes a standard uart interface and it is more or less silicon supplier independant, no ?

thanks for clarification.

best regards

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Anonymous
Not applicable

Have you checked the logic level voltages between the BCM and the USB serial device?  Table 13 in the Module technical reference describes the logic levels expected by the BCM.   Make sure your logic levels are matched.

I built a programming cable using an FTDI 3.3V USB UART device.  When the cable was 4 feet long it did not work.  When I shortened it to one foot long it works every time now.

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