Using ESP32 SDIO like SD card
Posted: Fri Jan 03, 2020 12:06 pm
Can SDIO slave block emulate SD card with file system like fat32?
Unfortunately, no. ESP32 SDIO slave supports only specific set of commands, such as IO read and write (CMD52, CMD53 in SD standard). SD cards need to implement a different set of commands, such as CMD17, 18, 24, 25 (single/multiple block read/write).
Since the commands are implemented by SDIO slave hardware, implementing the missing commands in software is not possible, unfortunately.