How do i pinout 1 bit mode on SD? 3 different ways?

[Andres_San]

Hi There

We want to use in our project 1 bit mode for SD handling, however, i've encountered 3 different ways of doing it browsing on the inet.

Asides connecting SDCLK, SDCLC:

Some people only use Data0 --> https://www.instructables.com/Select-SD ... for-ESP32/
Some people use Data0 and Data1 --> https://www.youtube.com/watch?v=e1xOgZsnAuw
Some people uso Data0, Data1 and Data2 --> http://www.hardwarebook.info/SDIO

So.. what the correct way of connecting 1 bit mode SD?

Best!

[ESP_igrr]

Hi Andres,

For 1 bit mode you need to connect D0 line between the host and the card, in addition to CMD and CLK. Also make sure the D3 line is pulled up on the card side, it is necessary so that the card doesn't enter SPI mode.

D1 might come into play when interfacing with an SDIO card (e.g. another wi-fi module), this line is used for SDIO interrupts. Data storage cards don't use interrupts, so this line isn't necessary in your case.

[Andres_San]

Thanks!! helped a lot =)