nRF52840 4-bit SDIO functionality (or other possibilities)?

[rf_az]

A project is currently utilizing an NXP module to access the SD card via 4-bit SDIO.  I am exploring the feasibility of integrating an nRF52840-based module, and have a few questions.

• First and foremost, does the nRF52840 support 4-bit SDIO?  There are a few older threads (like this one) that suggest it doesn't, but I'd like a definitive answer.
• If not, is the QSPI driver compatible with SDIO? This older thread is inconclusive and conflicting.
• The Infocenter has an SDIO driver page that describes it as a "2-wire serial interface driver".  Is there more documentation for this?  Any examples using it? 

Thanks in advance!

[Turbo J]

rf_az said:

does the nRF52840 support 4-bit SDIO? 

Nope, only 1-bit SPI. QSPI is also no-go - most commands are hard coded and not compatible with SD.

rf_az said:

The Infocenter has an SDIO driver page that describes it as a "2-wire serial interface driver". 

This has nothing to do with sdcard SDIO, quote from the header file: "2-wire serial interface driver (compatible with ADNS2080 mouse sensor driver)".

[rf_az]

Disappointing news, but thank you for the concise and conclusive answer!