Hi, Not very knowledgeable with this stuff, be kind please. :grin: I have a DC window motor, L298N H bridge motor control board, an UNO, a volume knob thing (potentiometer), power, and a dream... I would like to turn the knob and have the motor increase speed as I turn the knob in one direction. I would like the motor to return to 0 rpm as I turn the knob back the other way. Could I get assistance with (everything) the code and wiring? Thanks! Jim [20221121_225446]

This should be close: // https://forum.arduino.cc/t/take-2-dc-motor-control/1056594 // // Version YY/MM/DD Comments // ======= ======== ======================================================== // 1.00 22/11/22 Running code // 1.10 22/11/22 Added comments // #define STOP false #define RUN true #define ENABLED true #define DISABLED false #define LEDon HIGH #define LEDoff LOW #define RelayOFF HIGH #define RelayON LOW #define PUSHED LOW #define RELEASED HIGH //********************************************^************************************************ //Using the L293N motor driver const byte heartbeatLED = 13; //LED toggles, gives the user an indication that code executiing const byte motorLED = 12; //when the motor is moving this LED is ON const byte ePin = 9; //to ENA on L293N PWM motor speed control const byte pin2 = 7; //to IN2 on L293N const byte pin1 = 6; //to IN1 on L293N const byte leftLimit = 4; //limit switch +5V---[50k PULLUP]---Pin4---[N.O Switch]---GND const byte rightLimit = 5; //limit switch +5V---[50k PULLUP]---Pin4---[N.O Switch]---GND const byte potPin = A0; //motor speed adjust bool leftFlag = RUN; bool rightFlag = RUN; byte lastLeftLimit = RELEASED; byte lastRightLimit = RELEASED; int motorSpeed; const int window = 25; int centerLow = 512 - window; int centerHigh = 512 + window; //TIMER stuff unsigned long heartbeatMillis; unsigned long checkSwitchesMillis; unsigned long updateMotorMillis; // s e t u p ( ) //********************************************^************************************************ void setup() { Serial.begin(9600); pinMode(leftLimit, INPUT_PULLUP); pinMode(rightLimit, INPUT_PULLUP); pinMode(heartbeatLED, OUTPUT); pinMode(motorLED, OUTPUT); pinMode(pin1, OUTPUT); pinMode(pin2, OUTPUT); pinMode(ePin, OUTPUT); digitalWrite(pin1, LOW); digitalWrite(pin2, LOW); digitalWrite(ePin, LOW); //Arduino UNO R3 pin 9 PWM frequency of 30.64 Hz TCCR1B = TCCR1B & B11111000 | B00000101; // for pin 9 PWM frequency of 30.64 Hz } //END of setup() // l o o p ( ) //********************************************^************************************************ void loop() { //********************************* heartbeat TIMER //is it time to toggle the heartbeatLED (every 500ms)? if (millis() - heartbeatMillis >= 500ul) { //restart this TIMER heartbeatMillis = millis(); //toggle the heartbeatLED digitalWrite(heartbeatLED, !digitalRead(heartbeatLED)); } //********************************* checkSwitches TIMER //is time to check our switches ? if (millis() - checkSwitchesMillis >= 50ul) { //restart this TIMER checkSwitchesMillis = millis(); checkSwitches(); } //********************************* updateMotor TIMER //is time to up date the motor speed ? if (millis() - updateMotorMillis >= 50ul) { //restart this TIMER updateMotorMillis = millis(); int potPosition = analogRead(potPin); //******************** at center //are we at the center position ? if (potPosition > centerLow && potPosition = centerHigh) { //is the limit switch okay ? if (leftFlag == RUN) { motorSpeed = map(potPosition, centerHigh, 1023, 0, 255); analogWrite(ePin, motorSpeed); //move the motor CCW digitalWrite(pin1, HIGH); digitalWrite(pin2, LOW); digitalWrite(motorLED, LEDon); } //************ else { //the limit switch is operated //motor is turned OFF analogWrite(ePin, LOW); digitalWrite(pin1, LOW); digitalWrite(pin2, LOW); digitalWrite(motorLED, LEDoff); } } //******************** below center //are we below center position ? if (potPosition <= centerLow) { //is the limit switch okay ? if (rightFlag == RUN) { motorSpeed = map(potPosition, centerLow, 0, 0, 255); analogWrite(ePin, motorSpeed); //move motor CW digitalWrite(pin1, LOW); digitalWrite(pin2, HIGH); digitalWrite(motorLED, LEDon); } //************ else { //the limit switch is operated //motor is turned OFF analogWrite(ePin, LOW); digitalWrite(pin1, LOW); digitalWrite(pin2, LOW); digitalWrite(motorLED, LEDoff); } } //END of motor control } //********************************* //other non blocking code goes here //********************************* } //END of loop() // c h e c k S w i t c h e s ( ) //********************************************^************************************************ void checkSwitches() { byte currentState; //********************************* leftLimit currentState = digitalRead(leftLimit); //did this switch change state ? if (lastLeftLimit != currentState) { //update to the new state lastLeftLimit = currentState; //is this switch pushed ? if (currentState == PUSHED) { leftFlag = STOP; } else { //switch was released leftFlag = RUN; } } //END of this switch //********************************* rightLimit currentState = digitalRead(rightLimit); //did this switch change state ? if (lastRightLimit != currentState) { //update to the new state lastRightLimit = currentState; //is this switch pushed ? if (currentState == PUSHED) { rightFlag = STOP; } else { //switch was released rightFlag = RUN; } }//END of this switch } //END of checkSwitches() //********************************************^************************************************

Back of the pot labeled 4k7A FWIW

[image] Lskuared: Outside to outside 4.5kohm, no change on turn knob. Mid to right 0-4.5kohm turning knob end to end. Mid to left same as before but 4.5-0 turning knob. No. With the potentiometer set to the middle of the range, what is the resistance from the middle terminal to an outside terminal ?

Ok. Pot set to middle. Measure from center term to outside term 1 = 2306ohms. Measure from middle term to other outside term 2 = 2382 ohms. Not much for markings so best guestimate of center. [16691511896724996659199632317605] .

I did manage to design the gear interface part thing. The end result will be a thick disc that has 6-32 machine screws that protrude and engage the gear. [20221122_141414]

That potentiometer is linear, that's what you need. As discussed, will you be wanting limit switches ?

BTW Read through this post: [image] Share tips you have come across General Electronics Mounting Hardware on Panels, Chassis, etc. It is almost inevitable that when you measure and drill holes in surfaces to mount motors etc., you never get things perfect. The following procedure should give great results to get holes in the correct position. Measure the hole locations needed for your motor, transfer these to a graph paper template Use this template to make a rough pattern on a piece of scrap material Make the holes in this pattern oversized with the motor still being ab… [image]

Limit switches someday but if i can get the code now that wouod be great. I can just jump the 2 pinout locations for normally closed or nothing for normally open.

Worst case, if this doesn't work on the mill I can use it on my snow thrower project. Motorized chute control. Already installed the lights. Push joystick button, bam, lights. [20220223_132112] [20220317_021514] [20220317_021537] [20220212_123659] c9

[image] Lskuared: Motorized chute control. You obviously do not live in Florida. :cold_face:

Take 2, DC motor control

Projects Programming

LarryD November 22, 2022, 9:46pm 55

BTW

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Take 2, DC motor control

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