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Normal Counter Display showing Absolute Zero
In order to allow the user to precisely determine that the scaled count is exactly zero, rather than
a fractional value which displays as a zero in the current counting mode (Rounded or Truncated),
both the 4 and 2 digit versions have means to indicate that the count is exactly zero. The
Absolute Zero for the 2 digit display may be enabled or disabled by the user.
Before Zero (Slightly Negative)
2 Digit Display
4 Digit Display
Absolute Zero or Top Dead Centre (TDC)
2 Digit Display
4 Digit Display
After Zero (Slightly Positive)
2 Digit Display
4 Digit Display
One example of the utilization of absolute zero
A rotating tool is fitted with a Quadrature sensor which has 4 changes of state per revolution. In
order to show complete revolutions on the display, a denominator of 4 is chosen, and the rounding
mode is chosen as ‘Truncated’.
360 degrees Anticlockwise… Count = -4
display shows –1
270 degrees Anticlockwise… Count = -3
display shows –0
180 degrees Anticlockwise… Count = -2
display shows –0
90 degrees Anticlockwise…
Count = -1
display shows –0
0 degrees Top Dead Centre... Count = 0
display shows 0
or ≡
0 on the 2 digit version
90 degrees Clockwise…
Count = +1
display shows +0
180 degrees Clockwise…
Count = +2
display shows +0
270 degrees Clockwise…
Count = +3
display shows +0
360 degrees Clockwise…
Count = +4
display shows +1
4 Digit Counter Display with Overflowed Indication
If the overflow indicator is enabled and the count on the display has gone beyond the +/- 9999
full-scale range, and rolled over, the display will notify the user by flashing ‘X’ superimposed over
the sign on the left hand digit, and will continue to do so until either the count is zeroed or, the
power is removed from the unit.
Note that this rollover at +/-9999 will occur regardless of the position of the decimal point for
example at +999.9 +1 LS digit counts, or 99.99 +1 LS digit counts, or 9.999 + LS digit counts.
Note, for clarity the sign has been omitted from the left hand digit.
