SDIO start up clock rate

Hi,

Is there anyway to set the initial rate of the SDIO clock on the WP76 (R13.1/Legato 19.02)? It seems to default to 400Khz at the moment but I want it higher.

Regards

Matt

@mlw It’s normal that the SDIO clock starts at 400kHz during the init phase that includes speed detection. Then it goes to a higher speed. If it stays at 400kHz, it means that there was a detection issue with the SDIO chip.

indeed, but in my case the SDIO chip can only support 50MHz, and will generate an error at lower rates.

@deadpoolcode,

So the chipsets primary use for this interface was/is as an SD memory card, as a result, as per the standard which is discussed on the page below (in the electrical section), 400Khz has to be the starting frequency.

Until determining the card’s capabilities, the host device should not use a clock speed faster than 400 kHz.

Regards

Matt