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HP 48GX cpu clock speed
02-27-2020, 08:29 AM
Post: #5
RE: HP 48GX cpu clock speed
Hello,

The 48G chips uses an internal oscillator to generate the internal ~4mhz clock...
This oscillator is not tuned at the factory and, due to large variation in silicon wafers will be different from calculator to calculator. It will also change with temperatures as the physical characteristics of the oscillators component (resistors, NOT gates and capacitor) do vary with these...

Modern CPU uses PLL (Phase Locked Loop), which act as precise multiplicators of a precise cristal to set up clocks, but these are much more complex than a simple 2 NOT gate/1 resistor/1 cap system. Which is what the 48 uses.


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Cyrille

Although I work for the HP calculator group, the views and opinions I post here are my own. I do not speak for HP.
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Messages In This Thread
HP 48GX cpu clock speed - cdmackay - 02-26-2020, 07:21 PM
RE: HP 48GX cpu clock speed - SammysHP - 02-26-2020, 07:35 PM
RE: HP 48GX cpu clock speed - cdmackay - 02-26-2020, 07:42 PM
RE: HP 48GX cpu clock speed - cdmackay - 02-26-2020, 07:50 PM
RE: HP 48GX cpu clock speed - cyrille de brébisson - 02-27-2020 08:29 AM
RE: HP 48GX cpu clock speed - TomC - 02-27-2020, 05:40 PM
RE: HP 48GX cpu clock speed - cdmackay - 02-27-2020, 04:56 PM



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