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Timer Tick Interrupt

RTX51 Tiny uses the standard 8051 Timer 0 (mode 1) to generate a periodic interrupt. This interrupt is the RTX51 Tiny Timer Tick. Timeout and interval values specified for the RTX51 Tiny library routines are measured using the RTX51 Tiny Timer Tick.

By default, the RTX51 Timer Tick interrupt occurs every 10,000 machine cycles. So, for a standard 8051 running at 12MHz, the period of the timer tick is 0.01 seconds or a frequency of 100Hz (12MHZ / 12 / 10,000). The value may be changed in the CONF_TNY.A51 configuration file.


  • You may append your own code to the RTX51 Timer Tick Interrupt. Refer to the CONF_TNY.A51 configuration file for more information.
  • Refer to the discussion of Interrupts in the Overview for details on how the interrupt system is used by RTX51 Tiny.
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