diff --git a/board/freescale/imxrt1050-evk/README b/board/freescale/imxrt1050-evk/README
index f7e2894..a7e68fa 100644
--- a/board/freescale/imxrt1050-evk/README
+++ b/board/freescale/imxrt1050-evk/README
@@ -11,11 +11,11 @@
 
 - Flash the SPL image into the micro SD card:
 
-sudo dd if=SPL of=/dev/mmcblk0 bs=1k seek=1; sync
+sudo dd if=SPL of=/dev/sdX bs=1k seek=1; sync
 
 - Flash the u-boot.img image into the micro SD card:
 
-sudo dd if=u-boot.img of=/dev/sdb bs=1k seek=128; sync
+sudo dd if=u-boot.img of=/dev/sdX bs=1k seek=128; sync
 
 - Jumper settings: