Crystal Issue in Atmel AT89S8253?

Discussion in 'Embedded Systems and Microcontrollers' started by g_shyam1682, Feb 10, 2010.

  1. g_shyam1682

    Thread Starter New Member

    Jan 25, 2010
    Hello friends,

    I am using Atmel AT89S8253.
    Currently I am using crystal 20 MHz with 27 pf ceramic capacitor, I am facing following problems

    -- It dows processor speed upto 1/3. sometimes result it hang processor
    -- Sometimes crystal is defected.

    I am looking for option for same.

    so guys do you have any suggestion???

    Suggestion is highly appreciated
    Thanks in advance
  2. mik3

    Senior Member

    Feb 4, 2008
    You need two 27pF ceramic capacitors, from each pin of the crystal to ground. Also, some crystals, depending on their cut method, need a 25 Ohm resistor in series with one pin of the crystal and the microcontroller. You can find that information in the datasheet of the crystal.