SD reader does not work

Hello! I have an arduino mega and a card reader:
Connected as follows:
MOSI - 51
MISO - 50
SCK - 52
CS - 53

Standard examples for working with the SD card work correctly. In the firmware MARLIN the card reader also works, but when I fill in the firmware the REPETIER card is not visible. The card is formatted in FAT32, it has standard gcode files. In the configuration the support of the SD card is enabled. Help me please


  • Do you have also a lcd? Lcd configs often overwrite sd card settings. Also make sure to have sd detect pin set to -1 as your card does not have this.
  • Yes, i have display 2004 (work correctly).

    My settings in Configuration.h

    #ifndef SDSUPPORT  // Some boards have sd support on board. These define the values already in pins.h
    #define SDSUPPORT 1
    #define SDCARDDETECT -1
  • edited March 2017
    Although it is described #define SDCARDDETECT -1. The card reader starts working only after I lock pin 49 to ground
  • If in ui.h specify #ddefine SDCARDDETECT -1. The card reader starts to work always.
  • Ok, so it is lcd defintion overwriting your settings.
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