Tripped Up On an S08SH

Discussion created by Guest on Feb 15, 2010
Latest reply on Feb 15, 2010 by bigmac

I was about to post a question here when I finally realized the error of my ways, so I thought I'd post anyway in case someone takes the same path as me.

 

I'm converting some software from a QG8 to an SH8. I looked carefully at the ICS diagrams and the ICS registers. Yep, the same thing, so that part should be pretty much a copy & paste.

 

Uhhh, no. The DCO on an SH runs twice as fast as the DCO on a QG, and therefore the bus clock is 2x that of a QG. Two clues that I missed: 1. The DCO runs at 1024 times the reference clock vs 512 on the QG, and 2. max bus frequency spec on an SH is 20MHz vs 10MHz on a QG.

 

The simple fix is to keep BDIV at divide-by-2 and not change it to divide-by-1 like I was doing on the QG.

 

Think I've missed anything else? 

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