HT16562 Holtek Semiconductor, HT16562 Datasheet - Page 6

• Manufacturer Part Number: HT16562
• Description: 1/2 Duty VFD Digital Clock
• Manufacturer: Holtek Semiconductor

DataSheet.in
Time Adjustment Operation
Application Circuits
Note: Capacitor C9 and C10 can adjust the accuracy of frequency
Rev. 1.00
Hour/minute adjustment
Both the minutes and hour displays can be adjusted
separately or both together in a fast forward format.
The hour set pin, HS, and the minutes set pin, MS, are
used to make these adjustments. Both of these pins
are connected to internal pull-high resistors. Each
time one of these lines is pulled low, the respective
hour or minute value will increment by one, also if the
line is continuously held low then the respective value
will increment automatically at a rate of 2Hz. Both val-
ues will increment together if both lines are pulled low
simultaneously. Note that no carry functions will be im-
plemented when either the hour or minute value over-
flows.
Zero adjustment
A zero adjust function is also included within the de-
vice and is controlled by the ZA pin. This pin is con-
nected to an internal pull-high resistor. Pulling this line
low will reset both the internal minutes and seconds
value, however the way in which the display is reset
depends upon the present value of the display. If the
6
minute value is presently less than 30 the only the
second and minute values will be reset to zero and the
hour value remain unchanged. However if the minute
value is presently at a value of 30 or higher then when
the zero adjustment function is executed, a carry will
be implemented and the hour value will be incre-
mented by one. The following table illustrates a few
examples of this operation.
Hr.
1
2
2
2
2
3
Present Time
Min.
30
00
29
30
59
29
Zero Adjust Examples
Sec.
00
00
59
00
59
59
Hr.
2
2
2
3
3
3
After Zero Adjust
March 28, 2007
Min.
00
00
00
00
00
00
HT16562
Sec.
00
00
00
00
00
00