Re: 48g upgrade to 768k but only getting 640k? Message #4 Posted by Han on 14 Sept 2006, 6:34 p.m., in response to message #3 by caribet
That's for ALL HP48G/G+/GX PCBs as far as I know. Many of the current online guides or ones from the old newsgroups postings are wrong about the two resistors. If you read up on the hex-flop chip and understand how it works, then you can easily see why an RC (resistor + capacitor) circuit is needed there as opposed to two resistors. In short, it's to prevent the reset line of the hex-flop chip from resetting the bank-switching mechanism during a voltage fluctuation.
But as with the zener diode, many of these extra circuits were for "just-in-case" scenarios.
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