// OS_TMR_TICK = 250

#if defined(_PIC18) || defined(_PIC18I)   // PIC18 Hi-Tech
  PR2     = OS_TMR_TICK;                  // timer tick = 1000 instruction cycles
  INTCON  = 0xC0;
  TMR2IE  = 1;
  TMR2IF  = 0;
  T2CON   = 0x05;
  #if defined(_PIC18)
  __CONFIG(2,WDTDIS);
  #else
  __set_configuration_bits(CONFIG3H, WDT_OFF_3);
  #endif

#elif  defined(_PIC14)                    // PIC16 Hi-Tech (14-bit)
  OPTION  = 0b00000001;                   // timer tick = 1000 instruction cycles
  INTCON  = 0b11100000;
  __CONFIG(WDTDIS);

#elif  defined(_PIC12)                    // PIC12 Hi-Tech (12-bit)
  OPTION  = 0xD2;                         // timer tick = 1000 instruction cycles
  TMR0    = 0;
  __CONFIG(WDTDIS);

#elif  defined(_AVR_) || defined(_GAVR_)  // AVR IAR, AVR GCC
  TCCR0   =  (1 << CS01);                 // timer tick = 2000 instruction cycles
  TIMSK   |= (1 << TOIE0);
  ei();                                   // enable interrupts

#elif  defined(_MSP)                      // MSP430 IAR
  TACCTL1_bit.CCIE = 1;                   // it is enough of it only for C-Spy needs
  ei();                                   // adjust the timer settings for real work

#elif  defined(_51_)                      // 8x51 Keil
  TMOD    = 0x00;                         // timer tick = 8096 instruction cycles
  TCON    = 0x10;
  EA      = 1;
  ET0     = 1;

#elif  defined(_ARM_)

#endif