BCM20737S extra memory on SPI

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KoM_2154881
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Hi,

I would like to attach an external memory on the SPI bus and I am not sure if that is going to affect the operation of the internal memory.

The way I understand it, this shouldn't affect anything and when programming the code will still go the internal memory, is that correct?

Also, should I have any problems if I have both the SPI (for the memory) and UART (for talking to another MCU) interfaces enabled at the same time? Will, the processor

be able to handle everything without problems?

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I checked with the team and SPIFFY2 could be used if the memory you are accessing is ok with the slower 6MHz speed of the bus.  You would also have to write your own driver.

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MichaelF_56
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There are two SPI ports (SPIFFY 1 and 2).  SPIFFY 1 is the high speed one, but it shares pins with I2C, which is what the module uses to access the onboard EEPROM.

More here: How to set the SPI2 as the NVRAM Interface

These interfaces and their respective limitations are described here within the WICED Smart Hardware Interfaces

Leveraging external flash is described here: Re: External Serial Flash for wiced smart BCM20736​ and here: TAG3 Serial Flash Configuration

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Thank you for the response. I am going through the documents and I have a couple of questions.

We are thinking of using the internal EEPROM as is without changing anything. We are also using the I2C bus.

This way we can't use the SPIFFY1.

We want to have additional memory there, so we want to attach the memory chip in SPIFFY2.  Downloading and updating will happen as usual in the EEPROM and we can have the extra memory in SPIFFY2 for saving data. This should work without issues right?

Would it be better to use SPIFFY2 exclusively?

Sincerely,

Kostas

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Seems technically possible if you can find serial flash happy being accessed at 6MHz. I need to check around to see if anyone has ever used this interface to access external SFLASH.  I've personally only seen I2C used (memory and sensors can be used given addressing is setup correctly)

BCM2073XS GPIO Basics​ will provide some additional guidance on how to make sure the GPIOs are being used correctly.

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I checked with the team and SPIFFY2 could be used if the memory you are accessing is ok with the slower 6MHz speed of the bus.  You would also have to write your own driver.

Do you have any memories that you recommend?

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Unfortunately, we do not since this is not a common practice.

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