"Official" PLL init code

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"Official" PLL init code

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colinh
Contributor I
Hi

Does anyone know of either (a) some Freescale example code for setup of the PLL, or (b) a solid rationale for the NOPs in the following.  I have to justify (or otherwise) the presence of the NOPs in some code written by a guy who left the company.

Code:
PLL_ON;                         // macro to turn on PLL
#asm
    "nop";
    "nop";
    "nop";
    "nop";
#endasm
while((CRGFLG & 0x08) == 0){}   // poll for LOCK

 The logic behind this question is simple, if they should be there, then some justification should be made, if not they should be removed. Unfortunately the old saying "if it aint broke dont fix it" doesn't hold in this case :smileysad:

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kef
Specialist I
IIRC some old DP256 masksets have some PLL related issues.
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colinh
Contributor I
Thanks Kef

This has given me enough info to chase up Freescale to get the exact details regarding mask-sets etc.

Cheers
Colin

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