2Gbit NOR flash at QSPI has shifted Read data from flash

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

Vincent520 — Mon, 20 Mar 2023 11:09:50 GMT

It is likely due to incompatible action taken by nRF mcu and the expected by flash chip. I’m currently working on MT29F2G flash with nrf52840, the flash which is NAND 2Gbit flash, very similar to the one used by poster of this thread, the issue I’m seeing is the nRF mcu is sending 3 bytes address for the address, while the flash is expecting 2 bytes address, thus I’m having similar issue that the received data is a byte shifted than expected

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

AustinEngineer — Thu, 11 Nov 2021 15:23:49 GMT

Hi, were you able to get this working?

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

Marien — Sun, 16 May 2021 08:40:28 GMT

Hi Jorgen,
If I change NRF_QSPI_READOC_READ4IO; to NRF_QSPI_READOC_READ4O;
No I between 4 and O.
Than the divice works fine.
I don't know the difference, logic analiser shows the same 4 bit activity

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

Jørgen Holmefjord — Mon, 10 May 2021 14:17:50 GMT

There is also a nonvoltatile configuration register in the device where you can configure Quad I/O mode, and there is a command to enter Quad mode. Have you tried these? If the device is not configured to work in quad mode, the commands for quad read/write may not work as expected.

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

Marien — Thu, 06 May 2021 09:19:22 GMT

Yes, quad mode is enabled:
at: config.prot_if.readoc = NRF_QSPI_READOC_READ4IO;
checking this on the lines with a logic analiser confirms the quad mode: all lines show data...

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

Jørgen Holmefjord — Tue, 04 May 2021 15:32:52 GMT

Hi,

My point was not what the bit does, but what it does not do, i.e., enable quad mode. Have you done any other changes in the application to enable quad mode for the MT25?

If quad mode is not enabled, I would not expect correct behavior for quad reads. You should be able to find how to enable quad mode in the datasheet of your flash device.

Best regards,
Jørgen

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

Marien — Sun, 02 May 2021 20:31:04 GMT

Hi Jorgen, bit 6 manages the protected sectords in the MT25.
I checked this and turn it off.
Any other suggestion for the datashift problem?

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

Jørgen Holmefjord — Tue, 27 Apr 2021 09:50:40 GMT

Hi,

Is it possible that you have not enabled Quad mode correctly in your device?

The MX25 device has a "Quad Enable" field in bit 6 of the Status Register, which is used by the example application to enable Quad operations:

uint8_t temporary = 0x40;
// Switch to qspi mode
cinstr_cfg.opcode = QSPI_STD_CMD_WRSR;
cinstr_cfg.length = NRF_QSPI_CINSTR_LEN_2B;
err_code = nrf_drv_qspi_cinstr_xfer(&cinstr_cfg, &temporary, NULL);
APP_ERROR_CHECK(err_code);

I cannot see a corresponding filed in the Status register of your device:

Best regards,
Jørgen

RE: 2Gbit NOR flash at QSPI has shifted Read data from flash

Marien — Fri, 23 Apr 2021 21:04:08 GMT

additional:
at:   config.prot_if.readoc = NRF_QSPI_READOC_READ4IO; (default in the example)
the shift is 2 bytes.
at:  config.prot_if.readoc = NRF_QSPI_READOC_READ2IO;
the shift is 1 byte.
at:  config.prot_if.readoc = NRF_QSPI_READOC_FASTREAD;
no shift: Data is consistent.

strange... what is going woring in the quad and dual data transfer?