#define command     var00
#define parameter   var01
//set Spindle speed control via ET10 DAC channel #1
//Spindle Speed is given in **eparam** register

main()
{

  command=0x32; //EXT_ET10_DAC_OFFSET; set ADC offset register address
  parameter=0x800-(eparam/2)+(1<<12);
  //0x800 - is the middle of 12bits range - represents 0V
  //Eparam contains 12bits DAC value in 10V range, 
  //ET10 DAC setup in +10V...-10V range, so need half range (/2)
  //Encoder channel number is given in high 12 bits of 16bit word  -
  //Channel #1 is (1<<12).

  message=PLCCMD_SET_CNC_EXTVAR;    
  //setup Message register with command for access to [[External CNC Variables]]
  texit=timer+2;do{timer++;}while(timer<texit);
  //2ms delay to push the command from PLC to myCNC Core


  //**Set Spindle Speed** is an asynchronous operation. 
  //It's good to inform myCNC Software New Spindle Speed applied.
  //Send information about new Spindle Speed to myCNC Software
  //myCNC register #7371 contains actual Spindle Speed. 

  gvarset(7371,eparam);           
  timer=30; do { timer--; } while (timer>0); //Delay to push the Message to myCNC Software
  //A way to inform myCNC software about new Spindle Speed (to display on it DRO for example)


exit(99);  //normal exit.
};