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???
04/13/06 16:26
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#114233 - Divide-by-12 = Divide-by-(2*6)
Responding to: ???'s previous message
Erik said:
Have a look at fig.15 on page 12 of ch1 and come back with "there is a divide by 2 of the clock"

Kai Klaas said:
... Of course, this above mentioned flip-flop must be part of the internal divide-by-12 circuitry.


Quite so: on page 11 of the Philips document, it says:

Machine Cycles
A machine cycle consists of a sequence of 6 states, numbered S1 through S6. Each state time lasts for two oscillator periods. Thus a machine cycle takes 12 oscillator periods or 1ms if the oscillator frequency is 12MHz.
(my emphasis)

Thus the "state time" must involve a divide-by-two from the oscillator frequency...?


List of 21 messages in thread
TopicAuthorDate
Capacitor significance            01/01/70 00:00      
   Search            01/01/70 00:00      
   Why burden caps must not be omitted            01/01/70 00:00      
      Thanks: But still some more            01/01/70 00:00      
         because that is when the address need be            01/01/70 00:00      
   Divide dy 2            01/01/70 00:00      
      Where is this divide by 2?            01/01/70 00:00      
         Thank you SIR            01/01/70 00:00      
            Beware of applying specifics in general!            01/01/70 00:00      
            Re: clock division...            01/01/70 00:00      
               I suggest you do not            01/01/70 00:00      
                  Misleading information            01/01/70 00:00      
                     Divide-by-12 = Divide-by-(2*6)            01/01/70 00:00      
                        Oops - 1us, not 1ms!!            01/01/70 00:00      
                  not exactly ...            01/01/70 00:00      
               it would not be so simple            01/01/70 00:00      
      Clock division - in summary            01/01/70 00:00      
         Re: Clk division summary            01/01/70 00:00      
            Language?            01/01/70 00:00      
               ok ok one more help            01/01/70 00:00      
                  Links            01/01/70 00:00      

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