Arduino: L293D for a DC motor

L293D for a DC motor

A L293D motor controller chip and a DC motor.

I got fed up with indecipherable pinout diagrams within datasheets, so have designed my own that I think gives more pertinent information.

There are 3 wires connected to the arduino, 2 wires connected to the motor, and 1 wire connected to a battery.

A L293D motor controller chip - pinout diagram.
Green - connected to arduino.
Blue - connect to motor
Pink - connect to a battery +ve, eg 12 volt.

To use this pinout:
The left hand side deals with the first motor, the right hand side deals with a second motor.
Yes, you can run it with only one motor connected.

Arduino Connections
M1 PWM - connect this to a PWM pin on the arduino. They're labelled on the Uno, pin 3 is an example. Output any integer between 0 and 255, where 0 will be off, 128 is half speed and 255 is max speed.

M1 direction 0/1 and M1 direction 1/0 - Connect these two to two digital arduino pins. Output one pin as HIGH and the other pin as LOW, and the motor will spin in one direction. 
Reverse the outputs to LOW and HIGH, and the motor will spin in the other direction.

A L293D motor controller chip - pinout diagram.
Green - connected to arduino.
Blue - connect to motor
Pink - connect to a battery +ve, eg 12 volt.

To use this pinout:
The left hand side deals with the first motor, the right hand side deals with a second motor.
Yes, you can run it with only one motor connected.

Arduino Connections
M1 PWM - connect this to a PWM pin on the arduino. They're labelled on the Uno, pin 3 is an example. Output any integer between 0 and 255, where 0 will be off, 128 is half speed and 255 is max speed.

M1 direction 0/1 and M1 direction 1/0 - Connect these two to two digital arduino pins. Output one pin as HIGH and the other pin as LOW, and the motor will spin in one direction. 
Reverse the outputs to LOW and HIGH, and the motor will spin in the other direction.

The code below does not use a separate power supply (ie a battery), it uses instead the 5v power from the arduino. Note that this would be risky without the L293D controlling it. 
You should _never_ connect a motor directly to the arduino, because when you switch a motor off you get an electrical feedback. With a small motor, this will damage your arduino, and with a large motor, you can watch an interesting flame and sparks effect.

Wired up.L293D Pin : Arduino Pin1:32:53(DC motor +5V) 4(GND)5(GND)6(DC motor GND)7:48(+5V)9:610:811(DC motor #2 +5V)12(GND)13(GND)14(DC motor #2 GND)15:716(+5V)

This is the code that I used.

A L293D motor controller chip - pinout diagram.
Green - connected to arduino.
Blue - connect to motor
Pink - connect to a battery +ve, eg 12 volt.

To use this pinout:
The left hand side deals with the first motor, the right hand side deals with a second motor.
Yes, you can run it with only one motor connected.

Arduino Connections
M1 PWM - connect this to a PWM pin on the arduino. They're labelled on the Uno, pin 3 is an example. Output any integer between 0 and 255, where 0 will be off, 128 is half speed and 255 is max speed.

M1 direction 0/1 and M1 direction 1/0 - Connect these two to two digital arduino pins. Output one pin as HIGH and the other pin as LOW, and the motor will spin in one direction. 
Reverse the outputs to LOW and HIGH, and the motor will spin in the other direction.

/************************Exercise the motor usingthe L293 chip************************/#define ENABLE 3#define DIRB 4#define DIRA 5int i; void setup() {  //---set pin direction  pinMode(ENABLE,OUTPUT);  pinMode(DIRA,OUTPUT);  pinMode(DIRB,OUTPUT); Serial.begin(9600);}void loop() {  //---back and forth exampleSerial.println("One way, then reverse");  digitalWrite(ENABLE,HIGH); // enable on  for (i=0;i<5;i++) {    digitalWrite(DIRA,HIGH); //one way    digitalWrite(DIRB,LOW);    delay(500);    digitalWrite(DIRA,LOW);  //reverse    digitalWrite(DIRB,HIGH);    delay(500);  }  digitalWrite(ENABLE,LOW); // disable  delay(4000);Serial.println("fast Slow example");  //---fast/slow stop example  digitalWrite(ENABLE,HIGH); //enable on  digitalWrite(DIRA,HIGH); //one way  digitalWrite(DIRB,LOW);  delay(1000);  digitalWrite(ENABLE,LOW); //slow stop  delay(3000);  digitalWrite(ENABLE,HIGH); //enable on  digitalWrite(DIRA,HIGH); //one way  digitalWrite(DIRB,LOW);  delay(1000);  digitalWrite(DIRA,LOW); //fast stop  delay(3000);//Serial.println("PWM full then slow");  //---PWM example, full speed then slow  digitalWrite(ENABLE,HIGH); //enable on  digitalWrite(DIRA,HIGH); //one way  digitalWrite(DIRB,LOW);  delay(2000);  analogWrite(ENABLE,128); //half speed  delay(2000);  digitalWrite(ENABLE,LOW); //all done  delay(10000);}   

All the above is in the public domain. It's included here to show which PIN settings work with which code.

原文链接：
http://www.goodliffe.org.uk/arduino/dcmotor.php

A L293D motor controller chip - pinout diagram.
Green - connected to arduino.
Blue - connect to motor
Pink - connect to a battery +ve, eg 12 volt.

To use this pinout:
The left hand side deals with the first motor, the right hand side deals with a second motor.
Yes, you can run it with only one motor connected.

Arduino Connections
M1 PWM - connect this to a PWM pin on the arduino. They're labelled on the Uno, pin 3 is an example. Output any integer between 0 and 255, where 0 will be off, 128 is half speed and 255 is max speed.

M1 direction 0/1 and M1 direction 1/0 - Connect these two to two digital arduino pins. Output one pin as HIGH and the other pin as LOW, and the motor will spin in one direction. 
Reverse the outputs to LOW and HIGH, and the motor will spin in the other direction.