Quadrature hall encoder sequence problem

Using Arduino Motors, Mechanics, Power and CNC
1

Hi All,
I have a hall encoder gearmotor connected to an ESP32.
Motor is: https://uk.banggood.com/CHIHAI-MOTOR-GM25-370-DC-Gear-Motor-6V-100210300RPM-Encoder-Motor-p-1016183.html?ID=519629&cur_warehouse=CN

Using a simple test program:

const byte interruptPin = 5;
const byte otherPin = 4;
int valC1 = 0;
int valC2 = 0;

void setup() {
  Serial.begin(115200);
  Serial.println("Start");
  pinMode(interruptPin, INPUT);
  pinMode(otherPin, INPUT);
 
}
 
void loop() {
valC1 = digitalRead(interruptPin);
valC2 = digitalRead(otherPin);
      Serial.print(valC1);
      Serial.print(",");
      Serial.println(valC2);
 delay(100);
  }

Turning the shaft slowly I get this sequence:
11
01
11
10
Etc

It should be:
11
01
00
10
Etc

I’ve tried pull up and pull down resistors.
Anyone seen this before? Is it a faulty encoder or am I missing something?

Thanks in advance.
Sam

2

Sure sounds like a faulty encoder - perhaps the hall sensors are too close, the magnets too strong, causing the two channels to overlap twice as often as they should. Since the hall sensors seem accessible you could try
very carefully bending them a little back from the ferrite magnet ring?

3

If the magnet can be moved on the motor shaft, try sliding it away from the sensors.

You might need a miniature gear puller, though.

4

Ferrite is very brittle, and its likely cemented on, that will very liekly mean destroying the thing.

5

Thanks chaps. I'll give it a try.

6