Unusual clock with AT89C2051

Why unusual

Strangeness of this clock is in its expression of
numbers, which is realized using seven Leds.

Unusual clock with AT89C2051

Leds are located inside
a pipe, one above another and if we move Leds enough fast
left or right, we have a space where we can write numbers,
characters or anything else.

All these are possible only if we
turn on specific Leds at precision timing.

Moving LEDs left or right is
achieved using a steel plate, so we have to tense the
pipe in one direction (left or right) and let pipe to
vibrate by itself.

That "virtual display" has
resolution of 30*7 dots or five characters (5*7 with one
empty column).


Unusual clock with AT89C2051 #2

Unusual clock with AT89C2051 #3

To make this device you
will need:

A Piece of metal board (I used al-board 150mm*20mm)

Al-pipe in which are located LEDs (fi 10mm *145mm), it can
be of any material, but must be light and firm.

Plate steel 65mm*15mm*0.35mm

Unusual clock with AT89C2051 #4

On al-pipe you must drill 7 holes, where you will place 7
Leds. LEDs are connected with thin copper wire to circuit
board. You must have more patience cutting “piezo” to about
4mm and soldering it or glue it to steel plate.

“Piezo” is
significant piece in this device, as it is used for
triggering and helps us to know the position of Leds.
“Piezo” is a piezoelectric element and you can find it in
clocks, buzzers…


Unusual clock with AT89C2051 #5

Time adjusting

Setting time is not a complicated process, with key “Time” and
“Hour” you can change hours and with “Time” and “Min” – minutes.
The same thing applies also in alarm setting. Time and alarm
setting is possible only when the pipe vibrates with your help.
When the pipe be still, you can’t change time or alarm.

When time is identical to alarm setting you will see one neat
effect with LEDs.

Unusual clock with AT89C2051 #6


Download hex program code:

program SatAT89C2051

Download PCB/Schem layout:

sch, pcb – SatAT89C2051
– pcb file
in Protel 99 SE

SatAT89C2051.pdf – pcb file in PDF format

Unusual clock with AT89C2051 #7
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