74HC595 Sliding Tabs and LEDs

The 74HC595 is a very popular and widely used slider register building block. You can use slider registers for example for port expansion for outputs to convert a serial data stream into parallel or multiplexing.

Thanks to the chip, the LEDs can be controlled a little slower, so you can switch the LEDs only 500,000 per second instead of 8,000,000 per second, as would be the case without a chip. Nevertheless, this is still extremely fast, so you will never notice the difference with your eye.

4-digit 7-segment display.

7-segment indicators consist of 7 LEDs (segments), which are in the form of a "8". Most 7-segment displays actually have 8 segments, with a dot on the right side of the digit that serves as a decimal point.

When using a 4-digit 7-segment display, the displayed number is controlled by pin common anode or common cathode. If only one digit works, you can see all the numbers displayed with the principle of persistence of vision because the scan speed is so fast that you hardly notice the intervals.

By setting up the circuit and editing the program, users can make a simple display that shows certain numbers, or something more complicated, a count-up timer or an electric dice.

Step motor ULN2003A.

A stepper motor is a synchronous motor where the rotor can be rotated by a step-by-step rotating electromagnetic field of the stator coils by a minimum angle or multiple times. Stepper motors also exist in the form of linear motors.

With a computer-controlled stepper control, you can achieve very precise positioning and/or speed control, which is why stepper motors are the motor of choice for many applications for precise motion control.

The easiest way to connect a unipolar stepper motor to the motherboard is to use a breakout for the transistor array chip ULN2003A where voltage is applied to each of the coils in a specific order.