diff --git a/Demos/Device/ClassDriver/MassStorageKeyboard/Lib/SCSI.c b/Demos/Device/ClassDriver/MassStorageKeyboard/Lib/SCSI.c
index 897090c91b..e4bf4d602c 100644
--- a/Demos/Device/ClassDriver/MassStorageKeyboard/Lib/SCSI.c
+++ b/Demos/Device/ClassDriver/MassStorageKeyboard/Lib/SCSI.c
@@ -307,10 +307,10 @@ static bool SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* MSInterfaceInfo
 	uint16_t TotalBlocks;
 	
 	/* Load in the 32-bit block address (SCSI uses big-endian, so have to reverse the byte order) */
-	BlockAddress = SwapEndian_32(*(uint32_t*)&CommandBlock.SCSICommandData[2]);
+	BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
 
 	/* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
-	TotalBlocks  = SwapEndian_16(*(uint16_t*)&CommandBlock.SCSICommandData[7]);
+	TotalBlocks  = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
 	
 	/* Check if the block address is outside the maximum allowable value for the LUN */
 	if (BlockAddress >= LUN_MEDIA_BLOCKS)