Quad SPI mode on Hifive1

(Jakob Nyberg) #1

I am looking into using quad SPI to communicate with the flash memory on the hifive 1 rev b board, and have some questions.

On page 22 of the flash datasheet it is stated that the QE bit should not be set to 1 if WP# or HOLD# is tied directly to the power supply. Setting the QE bit is needed for some quad spi commands to work.

Looking at the schematics of the hifive it appears that HOLD# is indeed connected to a power supply. Does this mean that using quad SPI with the flash memory is not possible on the hifive? The flash also has a QPI mode which can be enabled using a command, but if one of the lines is connected to a power supply i have doubts if that would work either.