STM32H7 QSPI kernel frequency too slow leads to read errors ?

Hi @Gpeti​ ,

I assume that detailed question is Problems accessing QSI Flash with consecutive reads.

-Amel

From the STM32H7 user manual there is no timeout by default:

By default, the QUADSPI never stops its prefetch operation, keeping the previous read

operation active with nCS maintained low, even if no access to the Flash memory occurs for a long time. Since Flash memories tend to consume more when nCS is held low, the

application might want to activate the timeout counter (TCEN = 1, bit 3 of QUADSPI_CR) so that nCS is released after a period of TIMEOUT[15:0] (QUADSPI_LPTR) cycles have

elapsed without any access since when the FIFO becomes full with prefetch data.

From my understanding setting the timeout would not change anything as long as the CPU needs to access the memory

From what I see on the scope, when I do a 4KB memcpy, the STM32 sends a single read command. nCS remains active (ie. low) as expected.

The part is S25FL064L.

thank you