- Wed Mar 31, 2010 2:50 pm
#97479
Hi, everyone
i'm posting first time here :)
I have a problem with a 32768Hz crystal. I have set it up like shown on the picture I've provided and I divided the frequnecy with three 4024 7-bit (÷128) ripple counters. It works but the length of the "second" is too short (i'd say maybe 900ms), I noticed it by watching obviously but confirmed it with a stopwatch.. I don't get what is wrong.. I have some suspicions, though. I think the 1M resistor has got something to do with the time, because when I change its value the length of the time changes as well.. That makes me ask a question: how come the frequency can be dependant on the resistor, I thought the crystal has got its natural oscillating frequency..And if you're asking where did I get this configuration it's from A level Electronics book.
but yeah, I am a little confused.
hope you guys know what i'm doing wrong :)
thanks in advance
i'm posting first time here :)
I have a problem with a 32768Hz crystal. I have set it up like shown on the picture I've provided and I divided the frequnecy with three 4024 7-bit (÷128) ripple counters. It works but the length of the "second" is too short (i'd say maybe 900ms), I noticed it by watching obviously but confirmed it with a stopwatch.. I don't get what is wrong.. I have some suspicions, though. I think the 1M resistor has got something to do with the time, because when I change its value the length of the time changes as well.. That makes me ask a question: how come the frequency can be dependant on the resistor, I thought the crystal has got its natural oscillating frequency..And if you're asking where did I get this configuration it's from A level Electronics book.
but yeah, I am a little confused.
hope you guys know what i'm doing wrong :)
thanks in advance
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