Electronic LED clock

Even in my youth, I wanted to collect an electronic clock. It seemed to me that assembling the watch was the pinnacle of skill. As a result, I assembled a watch with a calendar and an alarm clock on the K176 series. Now they are already morally outdated and I wanted to collect something more modern. After a long search on the Internet (I never thought it was so hard for me to please;)) I liked this scheme. The difference from the above diagram is that a rare microcircuit is not used. TRIC6B595, and its composite and more powerful analogue on microcircuits 74HC595 and ULN2003... The fixes to the circuit are shown below.

Diagram of electronic LED clock creeping line

The author of the scheme dear OLED, the firmware is also his. The clock displays the current time, year, month and day of the week, as well as the temperature outside and inside the house with scrolling text. They have 9 independent alarms. It is possible to adjust (correct) the stroke + - a minute per day, select the speed of the line, change the brightness of the LEDs, depending on the time of day.

In the event of a power outage, the clock is powered either from an ultracapacitor (1 Farad capacity is enough for 4 days of power), or from a battery. Anyone who likes it, the board is designed to install both. They have a very convenient and intuitive control menu (all control is done with just two buttons). The following parts are used in the watch (all parts are in SMD cases):

Microcontroller AtMEGA 16A

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Shift register 74HC595

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Chip ULN2803(eight Darlington keys)

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Temperature sensors DS18B20(installed as an option)

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25 resistors 75 Ohm (standard 0805)

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3 resistors 4.7kOhm

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2 resistors 1.5 kOhm

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1 resistor 3.6 kOhm

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6 SMD capacitors with a capacity of 0.1 μF

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1 capacitor 220 uF

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Watch quartz for a frequency of 32768 hertz.

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Matrices 3 pieces of brand 23088-ASR 60x60 mm - common cathode

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Any boozer for 5 volts.

Printed circuit board for electronic LED clock creeping line

For residents of Ukraine, I will tell you, the matrices are in the store of the Lugansk radio market. The advantages of watches over other similar devices are the minimum of parts and high repeatability. The LED clock starts working immediately after the firmware, unless of course there are no jambs in the installation. The microcontroller is flashed in-circuit; for this, special pins are provided on the board. I was flashing with the Ponyprog program. Fuses screens for programs ponyprog and AVR are given below, the firmware files in Ukrainian and Russian are also posted, who is more familiar with what.

If you do not need temperature sensors, then they can be omitted. The watch automatically recognizes the connection of sensors, and if one or both sensors are missing, then the device simply stops displaying the temperature (if one sensor is missing, then the outside temperature is not displayed, if both, then the temperature is not displayed at all).

Homemade LED watch case

To demonstrate the work of the clock, a video is given, it is not of high quality, since it was filmed with a camera, but what is there.

Watch video

Four copies of these watches have already been collected, I present each one to relatives for their birthday. And everyone liked them very much. If you also wanted to collect this watch and have any questions, you are welcome to our forum. Respectfully yours, Sergei Voitovich ( Sergey-78 ).

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