Flash writer command Lists：
XLS2 - Write to the S-record format images to the Serial Flash.
XLS3 - Write to the raw binary images to the Serial Flash.
XCS - Erase the Serial Flash.
EM_DCID - Display the CID registers of eMMC.
EM_DCSD - Display the CSD registers of eMMC.
EM_DECSD - Display the EXT_CSD registers of eMMC.
EM_SECSD - Modify the EXT_CSD registers of eMMC.
EM_W - Write to the S-record format images to the user data area of eMMC, and the boot partition of eMMC.
EM_WB - Write to the raw binary images to the user data area of eMMC, and the boot partition of eMMC.
EM_E - Erase the user data area of eMMC, and the boot partition of eMMC.
SUP - Change the SCIF baud rate setting.
H - Display the command help.