Heyy im newbie and ask how to stop the continuous rotation servo to stop when i run demo?

Projects Programming
1 

#include <SoftwareSerial.h>
#include <CytronServoShield.h>



SoftwareSerial mySerial(2, 3); // ON_BOARD_TX, ON_BOARD_RX
CytronServoShield servo;

void callback(uint8_t servoId, servo_status_t status) {
  String error="";
  switch(status) {
    case CYTRON_SHIELD_SERVO_CHECKSUM_ERROR:
      error = "Checksum error";
      break;
    case CYTRON_SHIELD_SERVO_TIMEOUT_ERROR:
      error = "Timeout error";
      break;
    default:
      error = "Unknown error";
  }
  Serial.println(error + " from servo channel " + String(servoId) + " !");
}

void setup()
{
  //  Debug output from Serial Monitor with baudrate 9.6kbps
  Serial.begin(9600); 

  while(!Serial);
  
  Serial.println(F("Cytron Servo Shield Demo"));
  Serial.println(F("Make sure to set RX=D3 and TX=D2."));
  
  //  Initialize serial communication for UART with baudrate 9.6kbps
  mySerial.begin(9600);

  //  Initialize servo shield
  servo.init(&mySerial);

  //  Register error callback for troubleshooting purpose (optional)
  servo.registerErrorCallback(callback);

  // Set initial position for servo from all channels to 4000 (approximately 90 deg)
  // When next call servo.position or servo.angle, it will move to initial position/angle first
  // then move to target position/angle
  // You can either use setStartPosition or setStartAngle
  // by default, initial position/angle is 4000/90deg
  Serial.println(F("Set initial position to 0 deg for all channels."));
  servo.setStartAngle(ALL_CHANNELS, 0);
  // servo.setStartPosition(ALL_CHANNELS, CYTRON_SHIELD_180_LOWER_CAP);
  
  // Serial.println("Set initial position to 180 deg ...");
  // servo.setStartAngle(ALL_CHANNELS, 180);
  // servo.setStartPosition(ALL_CHANNELS, CYTRON_SHIELD_180_UPPER_CAP);
  
  // Set specific initial position/angle for single channel
  // eg:
  // Serial.println("Set channel 2 servo initial position to 45 deg ...");
  // servo.setStartAngle(CHANNEL_2, 45);

  //  Deactivate all servo motor channels on Shield servo, except for channel 1
  //  CHANNEL 1 - CHANNEL_8
  //  or use 1 - 8 as channels
  //  0 - OFF, 1 - ON
  Serial.println(F("Enable channel 1 only."));
  servo.setChannel(ALL_CHANNELS, OFF); 
  servo.setChannel(CHANNEL_1, ON);
  // servo.setChannel(1, 1);
  
  //  We set servo from Channel 1 to move to position 6000 (range 0 - 8000)
  //  We can also specify speed for servo movement (range 1 - 100, slowest - fastest)
  //  provide 0 to speed will cause servo to move instantly to target position

  //  Set position = 6000, speed = 25
  Serial.println(F("Move to position 6000 with speed 25."));
  servo.position(CHANNEL_1, 6000, 25); 
  // Wait until servo reaches around the target position (tolerance 100)
  while(servo.getPosition(CHANNEL_1) <= 6000 - 100);
  delay(1000);

  // Move to position 1000 instantly
  Serial.println(F("Move to position 1000 instantly."));
  servo.position(CHANNEL_1, 1000);
  // Wait until servo reaches around the target position
  while(servo.getPosition(CHANNEL_1) > 1000 + 100);
  delay(1000);

  // Now we try to move servo with angle input
  // We try to move servo to 180 deg with speed 100
  Serial.println(F("Move to angle 180 deg with speed 100."));
  servo.angle(CHANNEL_1, 180, 100);
  // Wait until servo reaches around the target position with tolerance 5 deg
  while(servo.getAngle(CHANNEL_1) <= 180 - 5);
  delay(1000);
  
  // We try to move servo to 0 deg instantly
  Serial.println(F("Move to angle 0 deg instantly."));
  servo.angle(CHANNEL_1, 0);
  // Wait until servo reaches around the target position
  while(servo.getAngle(CHANNEL_1) > 0 + 5);
  delay(1000);



  Serial.println(F("Demo completed!"));
  
}

//Main loop
void loop()
{
}
2

Welcome to the forum

As your topic does not relate directly to the installation or operation of the IDE it has been moved to the Programming Questions category of the forum

Please follow the advice given in the link below when posting code, in particular the section entitled 'Posting code and common code problems'

Use code tags (the < CODE/ > icon above the compose window) to make it easier to read and copy for examination

https://forum.arduino.cc/t/how-to-get-the-best-out-of-this-forum

In my experience the easiest way to tidy up the code and add the code tags is as follows

Start by tidying up your code by using Tools/Auto Format in the IDE to make it easier to read. Then use Edit/Copy for Forum and paste what was copied in a new reply. Code tags will have been added to the code to make it easy to read in the forum thus making it easier to provide help.

3

What angle value causes servo to stand still (should be close to 90)?

4

The getAngle function call only returns the angle you last directed the servo to turn to. It is not updated as the servo moves, so you can't use it in the way you are doing.

5

.................but, it's a continuous rotation servo, ie no feedback, no position reference.

6

wouldn't it be the neutral value corresponding to 1.5 msec (see Servo Control)

7

Those are equivalent, depends on how the servo is called. I think some servo functions interpret values outside 180 degrees as microseconds.

Added: from the header,

void write(int value);             // if value is < 200 it's treated as an angle, otherwise as pulse width in microseconds

But this is a weird one, read the code, it's all tnagked up with

# include <CytronServoShield.h>

and may be specific to one servo brand?

I see a range of 0 - 8000, IDK what that's all about.

  // Set initial position for servo from all channels to 4000 (approximately 90 deg)

which seems like the answer to the question posed. Of course this needs some kind of tuning, 3995? 4079?

a7

8

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.