nRF52840 SPIM3 @32MHz functionnal on Engineering sample B?

[Mickael]

HI there,

I read somewhere here that the SPIM3 bus would be capable of 32MHz operations in the "next" chip revision (that was 6 months ago).

Could you confirm that it is now the case with the Engineering Sample B? 

Thank you,

Mickael 

[Håkon Alseth]

Hi,

 

The SPIM3 is present for engineering B, but it has these erratas:

RX buffer error at 32 MHz operation

SPIM3 does not generate EVENTS_END and halts if suspended during last byte

SPIM3 events incorrectly connected to the PPI

 

The first one is the most crucial for 32M operation, effectively limiting the operation frequency down to 16M. You should have engineering C if you need to evaluate 32MHz SPI operations.

For Engineering C, the errata #189 "RX buffer error at 32 MHz operation" is fixed, as shown in this section of the errata document:

http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52840.EngC.errata/dita/errata/nRF52840/EngineeringC/latest/err_840_fixed.html?cp=2_0_1_0_2

Cheers,

Håkon

[Mickael]

Super thorough answer - Thanks a lot you, Hakon.

[Mickael]

Hi Hakon, another couple this topic too: 

Are there specific pins to be used to get the best of SPIM3? Or at least, could you share what pins were used to validate it? 

I hope they are not shared with the specific QSPI pins as we are planning to use both. 

Cheers,

Mickael