Arria 10 ASDATA Flash interface

Hi,

After some research and playing around I've managed to gain access to the pins in user mode using the Arria 10 primitives.

I am having issues trying to read/write the flash memory. The Micron device keeps returning all FF for every read of memory locations.

I can read device ID okay.

I can read flag status register okay.

I can read status register okay.

I can change between 4 byte address mode and 3 byte address mode and read back these flags from flag status register so I know I have some comms with the flash device and Arria 10.

When writing the flash this is the sequence I am using:
- Command code write enable.

- Read status register to check wr en latch bit set.

- Command code 4-byte page program with data sent to flash in this step being x"12"(cmd code) & x"0000_0000"(4-byte address) & x"0123_5678"(4 bytes of data). Using extended(normal) SPI mode, with DQ0 being SPI in and DQ1 being SPI out.

- Read status register to check wr en latch bit cleared and no error bits set.

- Read location in memory but data still x"FFFF_FFFF". Data sent to flash for read is x"13"(cmd code)& x"0000_0000"(4-byte address)& x"0000_0000"(clocks for read data return).

I have also tried these steps with an erase first, but seeing as the memory is already FF an erase should not be required and the same issue of FFFF persists?

I have also observed that sometimes the wr en latch bit is not able to be set with the wr en command unless I first read the flag status register. Is this normal?

I realise this might not be the correct forum for this as Micron flash issues might be outside of scope of Intel support but any help/suggestions will be greatly appreciated.