How to use OSPI with STM32L4R9 on custom board?

[Hzhan.2]

Hello,

As mentioned in Errata sheet of STM32L4xxx, the auto polling mode is not functional. This mode allows an automatic polling fully managed by hardware on the memory status register. 

The workout in the Errata sheet is to use memory-mapped mode, but all the ST examples use auto-polling mode, so I am wondering how I can use OSPI with STM32L4R9.

Thanks.

[Amel NASRI]

Hi @Hzhan.2​ ,

The errata sheet needs to be updated in order to say that Indirect mode can be used as workaround (besides to memory mapped mode).

In the STM32CubeL4 example (Ex: STM32Cube_FW_L4_V1.16.0\Projects\STM32L4R9I-EVAL\Examples\OSPI\OSPI_NOR_ReadWrite_DMA), the polling is implemented by software (see OSPI_AutoPollingMemReady implementation) thanks to the do..while loop of an indirect mode function (HAL_OSPI_Receive).

The function OSPI_AutoPollingMemReady  isn't implemented in the same way for STM32Cube_FW_H7_V1.8.0\Projects\STM32H7B3I-EVAL\Examples\OSPI\OSPI_NOR_ReadWrite_DMA for example as the limitation "Auto-polling mode not functional with new octal memories" was fixed for STM32H7B3's OSPI.

-Amel