PLL Calculator and 1 Mhz Oscillator

[rayhall]

In a recent discussion I was advize that I had the wrong PLL settings for 13 Mhz bus clock and to use the PLL Calculator. The problem is the PLL calculator will not accept an oscillator less then 2 Mhz.

The S12G128 internal oscillator runs at 1 Mhz. My only option was to select 2 Mhz and 26 Mhz. This gave me settings that resualted in the 13 Mhz frequency I required. When I tried the sugested settings given to me for 13 Mhz the S12G128 ran a lot faster. Is the source code for the PLL Calculator avaialble, so I can write a more flexable version.

Can I also request that when you reply to a discussion that you consider is solved, look at the post again the next day to see the reponce from the person who asked the orignal question. I am stating this new discussion as the above question was not solved.

Ray.

[iggi]

Ray,

i'm not aware of PLL calc for S12G devices.

I think you use the iPLL calc for S12XE and that's the right one. The only thing you should do is to switch to S12P and S12HY derivatives:

This will allow you to select 1MHz oscillator:

The CPMU module is the same on S12HY and S12G.

Regards,

iggi