Hardware Interrupt and I2C interference - how to resolve

Using Arduino Networking, Protocols, and Devices
8

Thanks Peter_n for your insight and assistance, I know its overdue, but just recently got everything working together :o

I have shortened the interrupt routines as much as possible as you have advised and did away with the string in the I2C code.

Even if its late, thought I would post where I am at now, that its all working together.

Below is the code as it stands now;

The Interrupt code of the Arduino Slave for the two interrupts and an additional interrupt with the I2C code:

//===========================================================
//=========  Direction Pin Chg interrupt routine    =========
//===========================================================
ISR (PCINT0_vect)                            {
    dir_pin_stat = digitalRead (dir_pin);
    if (dir_pin_stat == dir_XYZ) dir_pin_val = +1; else dir_pin_val = -1;     
                                             }
//===========================================================
//=========  Pulpresses_cntr interrupt routine    ========
//===========================================================
void Pul_void()                                                          {
        Pul_count_net = Pul_count_net + (long) dir_pin_val;
        pul_total     = pul_total     + (long) dir_pin_val;
        pul_odo++;
        if (pul_odo > 16000L) {  pul_odo=0L;  pul_odo_cm++;}
                                                                         }            
//===========================================================
//=========  H21A_total interrupt routine    ========
//===========================================================
void H21A_void()                                        {    
      if ( dir_pin_prev != dir_pin_val)                           {
      Pul_counter_error = Pul_counter_error + Pul_count_net;      }  // end if
    else                              { 
      Pul_counter_error = Pul_counter_error + Pul_count_net + (long)((dir_pin_val) * (-1L) * H21A_pul_width);
                                      }  // end else ..........   
      Pul_count_net = 0L;
      dir_pin_prev = dir_pin_val;
      H21A_total = H21A_total + (long) (dir_pin_val);     }

//===========================================================
//=========  I2C subroutine to send to Master    ============
//===========================================================
void send_i2c_data()                              {
    st_timer3 = micros(); 
  uint8_t buffer[16];  //uint8_t is a byte declaration
  int iij = 0;
  for (int ii = 0; ii < 8; ii++)         {
      buffer[iij] = val_arr [ii] >> 8;    //shifts the higer bits 8 places to right
      iij++;
      buffer[iij] = val_arr [ii] & 0xff;  //removes the left most 8 bits
      iij++;                             }
  Wire.write(buffer,16);
        st_timer3 = micros()-st_timer3;
                                                   }    // end void send_i2c_data()...............

Also the Master Teensy I2C code:

  uint16_t buffers  ;
  uint16_t buffers_inv  ;

  int available = Wire.requestFrom (5, (uint8_t)16);
  while(Wire.available())       {
          for (vl_cnt =0; vl_cnt < no_val-2; vl_cnt ++)               {  //no_val=10 in declaration part
              buffers = Wire.read() << 8 | Wire.read();
            if (buffers >= 32767)                         {
                buffers_inv = (~ buffers + 1);
                val_mstr [vl_cnt]  = -1 * buffers_inv;    }
            else val_mstr [vl_cnt]  = buffers;
                                                                      }
                                }  //....end... while(Wire.available())

Just getting the diy encoder cut on the CNC, and up and running soon, hopefully less crashes now :slight_smile: