The seven-segment numerical dispay |
A |
B |
C |
D |
E |
F |
G |
The seven-segment numerical dispay |
Referring to the diagram at left: clockwise, starting at the top, the seven segments of a single digit are called A, B, C, D, E, F and G. The Datel display module is designed such that the half digit displays the B and C segments only for the number 1 and the G segment for a minus sign. However, the driving circuit for the half digit contains all the information, and sends all the necessary pulses for each of the seven segments even though the segments A, D, E and F are absent. |
In case of the SH-T2, this means that when the half-digit driver tries to display the number 2 (out of range), only the B and G segments light up, simply because the A, E, and D segments that are also required to display the number 2 are absent. After 3 seconds of counting, the half-digit driver sends pulses to the A, B, C, D and G segments but again A and D are absent, and so on. All this, however, has no significance as far as testing the shutter speeds is concerned because while all this is happening the counter is already out of range, and whatever it displays is irrelevant. Also, please note that the above explanation is applicable to the Datel module in the SH-T2 tester and may not apply to any other half-digit displays. |
This explanation is only for the curious as it has no significance when testing shutter speeds. |
and how the half digit behaves in the Datel module |
