Digital LED clock Kit, with STC11FC2, 4digit

Digital LED clock with STC11FC2

Build:

The clock is implemented on a single-sided printed circuit board. The components needed to assemble the watch are divided into several groups and should be installed in this order

1. Resistors

2. Capacitors

3. Crystal

4. Resistor array

5. Transistor

6. Microswitches, piezo and terminal blocks

7. LED display

8. Sockets for microprocessor

9. Microprocessor.

Commissioning:

A 4 to 6V power source and DMM are required for commissioning.

First, check the soldering of all components. If everything is in order, clean the board of soldering residues, e.g. with alcohol or spirit.

Connect the supply voltage. - BEWARE OF THE POLARITY, THIS KIT DOES NOT HAVE PROTECTION AGAINST REVERSE POLARITY!

Current draw should be 20 to 40mA depending on the supply voltage. 12:59 will appear on the display.

To enter setting mode, long press the S1 (left) button. The letters A-H are displayed in the left part of the display, in the right part:

A: hours 00-23

B: minutes 00-59

C: sound signaling every hour ON/OFF (1=ON, 0=OFF)

D: alarm no. 1 ON/OFF (1=ON, 0=OFF)

E: 1st alarm clock 00-29

F: minutes of the 1st alarm clock 00-59

G: alarm no. 2 ON/OFF (1=ON, 0=OFF)

H: 2nd alarm clock 00-29

I: minutes of the 2nd alarm clock 00-59

A short press of button S1 moves between individual parameters (A-H), values ​​are set with button S2.

By pressing button S1 outside the setting mode, you can switch between HH:MM and MM:SS display, by long pressing S2 while displaying MM:SS you can

reset seconds for exact time synchronization.

When the clock is running, the colon between the segments flashes.

Technical specifications :

Digital LED clock with AT89C2051 W319

Power supply: 4 to 6V @ 20 to 40mA

Display HH:MM or MM:SS, in 24-hour mode.

2× alarm, whistle frequency resolution

Display color: Red

Height of display segments: 14 mm

Dimensions of the printed circuit board: 52 × 42 mm

Parts list:

R1, R2 - 10K

C1 - 10u

C2, C3 - 30p

C4 - 100n

PR1 - 1K

Y1 - 12MHz

U1 - STC11FC2

S1, S2 - microswitch

LS1 - piezo

Q1 - 8550

DS1 - display

J1 - terminal block

socket DIL20 1 pc

circuit board