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Topic: m2tklib and encoder problem (Read 1 time) previous topic - next topic


I have m2tklib working with my encoder. My code is below and is based on the sketch located here http://code.google.com/p/m2tklib/source/browse/arduino/LiquidCrystal/RecEnc/RotEnc.pde?r=27061897ecbcd61a7c9904d0934f173f57c8a120.

My encoder is not working smoothly. It is taking, on average, a 2-detent rotation of the encoder to register any change. There doesn't seem to be anything I can change within the sketch to make this work. I have had this encoder working smoothly in other sketches with code borrowed from here: http://www.buxtronix.net/2011/10/rotary-encoders-done-properly.html.

Is there anything I can do?

Code: [Select]
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include "M2tk.h"
#include "utility/m2ghnlc.h"

LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);

// Forward declaration of the toplevel element

// Simple dialog: Input two values n1 and n2

uint8_t n1 = 0;
uint8_t n2 = 0;

M2_LABEL(el_l1, NULL, "value 1:");
M2_U8NUM(el_u1, "c2", 0, 99, &n1);
M2_LABEL(el_l2, NULL, "value 2:");
M2_U8NUM(el_u2, "c2", 0, 99, &n2);

M2_LIST(list) = { &el_l1, &el_u1, &el_l2, &el_u2 };
M2_GRIDLIST(el_gridlist, "c2", list);
M2_ALIGN(top_menu, "-1|1W64H64", &el_gridlist);

// m2 object and constructor
// Note: Use the "m2_eh_4bd" handler, which fits better to the "m2_es_arduino_rotary_encoder"
M2tk m2(&top_menu, m2_es_arduino_rotary_encoder, m2_eh_4bd, m2_gh_nlc);

// Arduino Setup & Loop

void setup() {
  m2_SetNewLiquidCrystal(&lcd, 16, 2);

  // define button for the select message
  m2.setPin(M2_KEY_SELECT, 4);

  // The incremental rotary encoder is conected to these two pins
  m2.setPin(M2_KEY_ROT_ENC_A, 10);
  m2.setPin(M2_KEY_ROT_ENC_B, 9);

void loop() {
  if ( m2.handleKey() )



Maybe you can visit http://code.google.com/p/m2tklib/wiki/rotenc and check the ino files there. Will these files work better?

You can also tweak variables inside http://code.google.com/p/m2tklib/source/browse/dev/arduino/m2esarduino.c:
Try to use smaller values for
Code: [Select]


Finally you can rewrite "uint8_t m2_es_arduino_rotary_encoder(m2_p ep, uint8_t msg)" and replace the internal rotary encoder code with something more suitable: http://code.google.com/p/m2tklib/source/browse/dev/arduino/m2esarduino.c



Thanks for the tips! I have it working reasonably well now.

Initially I reduced the debounce and division variables you suggested down to 1. It was working ok but would usually miss an event on a change in encoder direction. I tried v2 of the encoder file (at http://code.google.com/p/m2tklib/wiki/rotenc) and found it to be similar.

Then I noticed that the m2esarduino.c file contained both versions of the encoder state table. I changed the if/else statement so that it would use the v1 table and that got it working near perfect. I have since had to increase the debounce (still playing around with it) but it is much better.


have a problem with low speed encoder.
This change did not help
How to Increase the speed of scanning speed?

Regards this KY-040 Rotary Encoder

thank you very much.

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