AT89C2051 Six digital clock kit singlechip 6 LED clock electronic production of bulk DIY

51 MCU-controlled digital clock, kit with circuit diagrams, a full set of components and circuit boards.

I. Description
STC digital clock, the control chip adopts STC single-chip microcomputer, the digital tube adopts three two-digit common anode type 0.36 inches LED digital tube, the display resolution is high, because it is the scanning method, so each adcdefg of each digital tube adopts bus parallel connection, changing R1 -The resistance of R7 can change the display brightness. The S1 key is used to calibrate the time, press and hold for more than 2 seconds to calibrate the time state and shift and exit. Quick touch is used to adjust the time resistance. This circuit has added a 3V backup battery. When the power is cut off, the SCM adopts a backup battery to supply power. The clock will not stop, but the digital tube will not display. The standby battery will lose its function after the call. The microcontroller will use external power supply and the digital control will display normally.
Note: If the digital display is abnormal, please disconnect the power supply, take out the backup battery, and then re-install it, and the power will return to normal.

Note:
1. This product is a spare part, it needs the buyer's own welding assembly, there is a program in the MCU, and the welding can be assembled to work.
2. Kit does not contain an external power supply

Second, the assembled finished product picture