QSPI Flash compatibility W25M02GVZEIG

RE: QSPI Flash compatibility W25M02GVZEIG

Jørgen Holmefjord — Fri, 12 Feb 2021 11:11:43 GMT

Looking further into this, I'm not sure that the flash chip is fully compatible with the QSPI interface, see this thread for some similar questions.

I tested the XIP example in our SDK with the on-board flash chip on the nRF52840 DK, and I cannot find a matching instruction format in the datasheet you provided:

RE: QSPI Flash compatibility W25M02GVZEIG

HurleyResearch — Mon, 08 Feb 2021 22:35:34 GMT

Thanks so much for your reply, I've got another question and could use your expertise.

If I use continuous read mode (BUF=0), the address bits are all dummy.

I assume that XIP will map the external flash data to the nRF5340 memory space (read only of course). Will I still be able to access the external flash memory the same as the internal flash memory, by simply using it like any other memory location? I'm failing to see how the nRF will know where (at which address) in external flash, to read, when I attempt to access a given address within the XIP mapped space.

Any hits will be appreciated, but I will go ahead and experiment with continuous read (BUF=0) mode. Thanks!

RE: QSPI Flash compatibility W25M02GVZEIG

Jørgen Holmefjord — Mon, 08 Feb 2021 16:03:56 GMT

Hi,

If I read the datasheet of the flash device correct, the "Instruction Set Table 1" in section 8.1.2 seems to match the nRF5340 QSPI documentation. According to the datasheet, you should be able to set the flash chip in Continuous Read mode by writing the BUF = 0, even if you have the xxIG model which powers up with BUF = 1.

Best regards,
Jørgen