SunFounder R3, Manual

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SunFounder uno-and-mega-kit
• SHcp : Time sequence input of shift register. On the rising edge, the data in shift register moves successively
one bit, i.e. data in Q1 moves to Q2, and so forth. While on the falling edge, the data in shift register remain
unchanged.
•
STcp
: Time sequence input of storage register. On the rising edge, data in the shift register moves into memory
register.
• CE : Output enable pin, active at low level.
• DS : Serial data input pin
• VCC : Positive supply voltage.
• GND : Ground.
Example
• Lesson 18 74HC595 (Mega Board Project)
• Lesson 23 Simple Creation - Digital Dice (Mega Board Project)
• Lesson 18 74HC595 (R3 Board Project)
• Lesson 23 Simple Creation - Digital Dice (R3 Board Project)
2.10 L293D
L293D is a 4-channel motor driver integrated by chip with high voltage and high current. It’s designed to connect
to standard DTL, TTL logic level, and drive inductive loads (such as relay coils, DC, Stepper Motors) and power
switching transistors etc. DC Motors are devices that turn DC electrical energy into mechanical energy. They are
widely used in electrical drive for their superior speed regulation performance.
See the figure of pins below. L293D has two pins (Vcc1 and Vcc2) for power supply. Vcc2 is used to supply power
for the motor, while Vcc1 to supply for the chip. Since a small-sized DC motor is used here, connect both pins to +5V.
The following is the internal structure of L293D. Pin EN is an enable pin and only works with high level; A stands for
input and Y for output. You can see the relationship among them at the right bottom. When pin EN is High level, if A
is High, Y outputs high level; if A is Low, Y outputs Low level. When pin EN is Low level, the L293D does not work.
2.10. L293D 25