For this week assignment I tryed to control the 5V servo motor Sg 90. For control was use the Attiny 45 microchip, and for design the board the Kicad software.

Components:

For design the schematic is important to know the pinout of the micrichip: So, in this example I connect the PWM output (for control the servo, the others outputs are ground and current) of the servo with the pin 3 (physically the pin 2) of the Attiny 45.

In Kicad is necesary to assign the footprints to the components in the schematic construction.

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The schematic

The board: In Kicad (board framework) for print it, I select the layers for traces and interior and export (red and yellow) as PNG, then process in Mods and generate a .rml file.

Once I have the .rml files, I work with Roland Monofab SRM 20 for machining the board.

Finally I soldered de components.

Then, I used the Arduino IDE for load the program in the microchip. For this process I use the AVR ISP as programmer, so I set it in the Arduino IDE.

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#include < SoftwareServo.h > 

SoftwareServo myservo;                 // create servo object to control a servo 
                                       // a maximum of eight servo objects can be created 

int pos = 0;                           // variable to store the servo position 

void setup() 
{ 
  myservo.attach(3);                  // attaches the servo on PB3 to the servo object 
  //myservo.attach(4);                  // attaches the servo on PB4 to the servo object (i didn´t use this pin)
} 

void loop() 
{ 
  for(pos = 0; pos < 180; pos += 1)  // goes from 0 degrees to 180 degrees 
  {                                  // in steps of 1 degree 
    myservo.write(pos);              // tell servo to go to position in variable 'pos' 
    SoftwareServo::refresh();        // must call at least once every 50ms or so to keep your servos updating
    delay(15);                       // waits 15ms for the servo to reach the position 
  } 
  for(pos = 180; pos>=1; pos-=1)     // goes from 180 degrees to 0 degrees 
  {                                
    myservo.write(pos);              // tell servo to go to position in variable 'pos' 
    SoftwareServo::refresh();
    delay(15);                       // waits 15ms for the servo to reach the position 
  } 
}