@echo off
set NUM=0 1 2 3 4 5 6 7 8 9 A B C D E F
:loop
for %%x in (%NUM%) do (
    for %%y in (%NUM%) do (
        color %%x%%y
        ping 127.0.0.1 -n 1 -w 500> nul
    )
)
goto loop