SPI External Flash NRF52

[Srikar]

Hello, Am working on NRF52 interface via SPI to Micron N25Q flash . Am able to identify flash by reading chip identification correctly and after this to test memory writing to 16 bytes data to flash and then reading 16 bytes.Both reading and writing are successful . Issue is always read returns data as 0xFF .

Interface Digram

• N52_SPI_CLK -----------> N25Q_CLOCK (8 MHz)
• N52_MOSI -----------> N25Q_DQ0
• N52_MISO <----------- N25Q_DQ1
• N52_SPI_CS <----------- N25Q_CS
• N25Q_WP (Pull up)
• N25Q_HOLD(Pull Up)
• MISO <----------- DQ1

I have also tried external pull down SPI_CLK ,but no change. If any ideas on this issue will be appreciated.

[endnode]

Hi Srikar,

If I remember correctly you need to enable write by specific command (usually called WRITE ENABLE) which sets WEL bit (flag in registers) before any PROGRAM/ERASE/WRITE command. Also double check that HOLD and WP (Write Protect) pins are at the right state (I guess it's HIGH). My feeling is that this is rather question related to Micron then Nordic so you might better seek support on their forum;)

Cheers Jan

[Jørgen Holmefjord]

Can you upload some code showing how you configure the device, and how you perform read and write operations? Are you using any driver or SPI directly? Which SDK are you using?

[Srikar]

N52_SPI_CS should low and not be changed during writing address and data to flash

[arjun]

Hi Srikar,

I am also facing problem in performing write operation. Could you explain how to prevent SPI_CS from going high. Do I need to change any settings in SPI library.

Thanks