Delay

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Delay

  1. 1. Delay Calculation in 8051
  2. 2. Machine cycle vs Clock cycle <ul><li>The time between two adjacent pulses of the oscillator is the clock cycle </li></ul><ul><li>Whereas 8051 requires 12 clocks (T-states) to execute a single machine cycle. So the clock cycle scaled down by 12 and hence machine cycle = clock cycle/12 </li></ul>
  3. 3. Delay calculation <ul><li>For 8051, </li></ul><ul><ul><li>The clock frequency is 11.059MHz </li></ul></ul><ul><ul><li>The machine cycle frequency is 11.059MHz/12 = 921.6kHz. </li></ul></ul><ul><ul><li>So machine cycle is </li></ul></ul><ul><ul><ul><li>1/921.6Khz = 1.085microseconds </li></ul></ul></ul><ul><ul><ul><li>To get 1 sec delay, 1/1.085microseconds = 921583 </li></ul></ul></ul>

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