I can not read SD_card.The debug output reads: "SD.begin() failed". #22
Description
i can not read SD_card,i need your help.
SD.begin(SD_SELECT) allways return false(Parselni.cpp: line 73 )
We know that SD_SELECT in the program is assigned the value of BUILTIN_SDCARD, and we tried to find the definition of BUILTIN_SDCARD. We learned that this value is not defined by the user but is inherent to the Teensy board. We added a print statement and found that BUILTIN_SDCARD is 254, and the CS pin in the SPI setup reads 3.3V instead of 0V. So far, we don't understand why SD.begin(SD_SELECT) returns false. This makes it difficult to proceed with our replication work because we cannot read the SD card's configuration parameters. Are there any solutions?