Bill Greiman

Actually a number of board packages use an SdFat wrapper for their SD.h. Arduino still used a 2009 version of SdFat. Teensy uses a more recent version of SdFat. ESP2866...

I will soon add this change to several others for SdFat V 2.1.2.

SD cards require full duplex SPI. The card looks at MOSI while it write to MISO. ESP quote: > While in general, speeds up to 80MHz on the dedicated SPI...

Probably best to use the ESP SD library. I don't want to waste time trying to support SdFat on ESP32, there are too many conflicts.

Unfortunately the 4-bit driver would need to be rewritten to get high speed in most programs using smaller reads and writes. I rewrote the driver for Teensy 3.x and 4.x...

I was talking about the sdmmc driver in esp-idf. It is extremely slow for small transfers, For writes of 512 bytes, only a few KB/sec. Print and small binary writes...

I tried a medium quality Samsung 64GB UHS-I microSD with CrystalDiskMark on Windows. Result is read 93 MB/sec write 88 MB/sec. About the same for SanDisk UHS-I card, read 95...

Read will also be slow. Most transfers are one sector and at best esp-idf will probably be under 1 MB/sec. I get about 2 MB/sec using SPI on the new...

@Miguel0101, I don't know if ESP32 has kernel support for USB MSC. If it does you can modify the above example to wrap the ESP32 API. I can't help since...

Have the author of WebServer fix the program to use long file names. `file.name()` returns a pointer to a 12 character 8.3 short file name. I suspect major changes would...