Canon EOS M200 Advanced User's Manual page 109

If the lowest f/number blinks, it indicates underexposure. Turn the <6> dial to
z
set a slower shutter speed until the aperture value stops blinking or set a higher
ISO speed.
If the highest f/number blinks, it indicates overexposure. Turn the <6> dial to
z
set a faster shutter speed until the aperture value stops blinking or set a lower
ISO speed.
Shutter Speed Display
For example, "0"5" indicates 0.5 sec. and "15"", 15 sec.
z
Shutter-priority AE Mode (Tv)
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