[code]
/*
Created by ArduinoGetStarted.com
This example code is in the public domain
Tutorial page: https://arduinogetstarted.com/tutorials/arduino-stepper-motor-and-limit-switch
*/
#include <ezButton.h>
#include <AccelStepper.h>
#define DIRECTION_CCW -1
#define DIRECTION_CW 1
#define STATE_CHANGE_DIR 1
#define STATE_MOVE 2
#define STATE_MOVING 3
#define MAX_POSITION 0x7FFFFFFF // maximum of position we can set (long type)
ezButton limitSwitch_1(A0); // create ezButton object that attach to pin A0;
ezButton limitSwitch_2(A1); // create ezButton object that attach to pin A1;
AccelStepper stepper(AccelStepper::FULL4WIRE, 7, 6, 5, 4);
int stepperState = STATE_MOVE;
int direction = DIRECTION_CW;
long targetPos = 0;
void setup() {
Serial.begin(9600);
limitSwitch_1.setDebounceTime(50); // set debounce time to 50 milliseconds
limitSwitch_2.setDebounceTime(50); // set debounce time to 50 milliseconds
stepper.setMaxSpeed(500.0); // set the maximum speed
stepper.setAcceleration(50.0); // set acceleration
stepper.setSpeed(100); // set initial speed
stepper.setCurrentPosition(0); // set position
}
void loop() {
limitSwitch_1.loop(); // MUST call the loop() function first
limitSwitch_2.loop(); // MUST call the loop() function first
if (limitSwitch_1.isPressed()) {
stepperState = STATE_CHANGE_DIR;
Serial.println(F("The limit switch 1: TOUCHED"));
}
if (limitSwitch_2.isPressed()) {
stepperState = STATE_CHANGE_DIR;
Serial.println(F("The limit switch 2: TOUCHED"));
}
switch (stepperState) {
case STATE_CHANGE_DIR:
direction *= -1; // change direction
Serial.print(F("The direction -> "));
if (direction == DIRECTION_CW)
Serial.println(F("CLOCKWISE"));
else
Serial.println(F("ANTI-CLOCKWISE"));
stepperState = STATE_MOVE; // after changing direction, go to the next state to move the motor
break;
case STATE_MOVE:
targetPos = direction * MAX_POSITION;
stepper.setCurrentPosition(0); // set position
stepper.moveTo(targetPos);
stepperState = STATE_MOVING; // after moving, go to the next state to keep the motor moving infinity
break;
case STATE_MOVING: // without this state, the move will stop after reaching maximum position
if (stepper.distanceToGo() == 0) { // if motor moved to the maximum position
stepper.setCurrentPosition(0); // reset position to 0
stepper.moveTo(targetPos); // move the motor to maximum position again
}
break;
}
stepper.run(); // MUST be called in loop() function
}
[/code]
You posted a pretty picture but it is of no use to me. Posting a schematic with all the connections as you have wired it will help a lot. Include links to technical data on all of the hardware items. Links to axon are about useless.
Suitable for two-phase and four-wire stepper motor
Board with two DRV8825 driver chip and a heat sink has been mounted.
Input VoltageοΌ8.2-45V DC (Just power the stepper motor driver), 1.6A output current per coil
Driving Pins: D4,D5,D6,D7,D8,D12
Squeeze connector, quite easy and convenient.
8 channel digital I/O pins & 6 channel Analog input pins
DRV8825 Microstepping bipolar stepper motor driver
Six different microstep resolutions (full-step, 1/2-step, 1/4-step, 1/8-step, 1/16-step, 1/32-step)
Compatible with Arduino UNO R3, Leonardo, Mega and other controllers, with full port extensions. Support XBee, XBee Wi-Fi, Bluetooth and RF modules, ensure that the needs of your wireless communications.
There is a switch on the board Xbee wireless interfaces corner. PROG stop wireless module, available USB programming. RUN time can use the wireless communication module.
Hybrid Stepper Motor 0.5Nm NEMA17 0.9 deg/step 42BYGHM809
for interest sake this was the pretty picture from ArduinoGetStarted.com where the code and
instruction were (their wiring on the limit switches
seemed weird, i still tried it, it didn't work)
case STATE_MOVE:
targetPos = direction * MAX_POSITION;
Serial.print("case STATE_MOVE, current target position = ");
Serial.println(targetPos);
stepper.setCurrentPosition(0); // set position
stepper.moveTo(targetPos);
//delay(50); // just in case the serial port gets flooded
stepperState = STATE_MOVING; // after moving, go to the next state to keep the motor moving infinity
break;
You may need to slow execution down (with a delay(), just for development) to avoid flooding the serial port.
See post #9. I actually put the prints in the STATE_MOVE case and you will see the results printed in serial monitor. To copy for us to see, highlight some of the output and hit ctrl-c to copy and then paste the copied text into a post.
Can someone explain to me the logic behind debouncing a limit switch.
My pea-brain tells me that once the switch opens it must be at the limit.
So why debounce. Do you expect another limit behind the limit?
That needless debounce code might also interfere with stepper speed.
Leo..
If the first action is the important one, debounce is not necessary. Another function of software debounce is to verify that the closure was a valid switch action and not noise, but for a limit switch I guess you would want to stop the motor first and ask questions later.
I am a fan of hardware debounce. I usually get flamed for saying this but I don't much care. That is how I have been doing it for near half a century and I don't plan to stop. I have found that if a 0.1uF cap won't debounce a switch then it is garbage.
I am a fan of hardware be-bounce as well. Very easy to do and reduces one source of gremlins.
Though may not matter much for a limit switch, except if using it to zero out your axes, may get minute errors. Which again may or may not matter depending on how much your program is relying on machine zero.
I don't like running hot wires all over the machine. Seems, to me, running ground to the switches is somewhat safer. Every 3D printer that I have worked on uses grounded switches so there must be something to it.
Yes, IMHO the switch should be between pin and ground,
with internal pull up, and a 10n cap across the switch to kill RF.
Normally closed, and opening when the limit is reached.
Leo..
