Re: I can't drive 95....

Smoking whiskey, drinking cocaine... I got me a feeling, XGA is driving me insane...

UZ, XGA-2 has a whoppin' 4MHz xtal on it, probably to act as a reference for the internal PLL.

Assume that the PLL is designed for stability. The division factor applies to the PLL output, NOT the 4MHz reference. So the PLL native output is 16x to 32x of the xtal.

90.00 x DF - 65 = 25

Oddly, for a PEL freq of 65MHz, the index would be 0, and for 128MHz, the index would be 63.

Louis Ohland wrote:
> Frequency Index = (f × Division Factor) - 65
where f is the PEL Frequency required.

FR Field Division Frequency Range
(binary) Factor

0 0 4 16.25MHz to 32.00MHz in 0.25MHz increments
0 1 2 32.50MHz to 64.00MHz in 0.50MHz increments
1 0 1 65.00MHz to 128.00MHz in 1.00MHz increments
1 1 - Reserved
.

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