Korg EMX1 Service Manual page 19

7."<NAND> UserLd"
8. "<NAND> Chking"
NOTE: If the step stops any of the above indications in the display, press
[SHIFT]+[15].
If the system data is loaded correctly, "Valv Wup ***sec"(000-160sec) is
indicated in the display.
If any other message is displayed such as "@@@@@ x:$$$", it might be an
error.
Wait until the tube test counter is displayed as "000sec" (approx 160 seconds
later). Then, please proceed to the Tube calibration test.