External memory

[lgs]

Can the nFR52840 connect the FRAM memory by the SPI or QSPI interfaces? The document describes it can connect the flash memory.

[Jørgen Holmefjord]

Hi,

The nRF52840 should be able to connect to and control any SPI peripheral devices. The QSPI interface is designed to interface external flash devices. If it is compatible with the interface of your FRAM memory depends on the memory. You need to check the datasheet of the memory of interest and compare it to the Instruction set defined in the QSPI peripheral in nRF52840.

Best regards,
Jørgen

[Jørgen Holmefjord]

Hi,

Nordic does not have any ICs with built-in FRAM. As you can read for the Mesh SDK documentation, worst-case lifetime for nRF52 with default configuration is over 50 years. Unless you have other settings that will require increased flash write/frequency, this should not be a concern.

Best regards,
Jørgen

[lgs]

Thanks. Now I want to construct a mesh network in an intermittent environment. You know the device will power off and power on frequently, I need to store the communication statin in the memory frequently. The SDK document says "The flash hardware can withstand a limited number of write and erase cycles. As the Bluetooth mesh stack uses the flash to store state across power failures, the device flash will eventually start failing, resulting in unexpected behaviour in the Bluetooth mesh stack." So, I am not sure whether I can deploy my programme on it or not. 

[Jørgen Holmefjord]

I would recommend you to create a new ticket if you have questions about the Mesh SDK and flash writes. This is off topic for this ticket's subject.