Erik,

I read your postings on the Philips forum.

Well, just to be sure I made two new chips from scratch, one with a x12 and one with a x6 clock setting, still without any difference.

The thing is that in FM it's not even possible to change to x12 clock; the default setting, as you indicated earlier, IS x6 clock. If I use the non-H version to change the clock mode, this obviously doesn't do anything (the chips are different). However, my parallel programmer simply reports the setting back on the H-device. Can you still follow?

What I will try next is to use the FM command line interface; no idea if this would work, but if it doesn't I simply move back to changing the software. Allows me to re-use the hand-full of micro's I now have with blown (or not blown? I don't know ..) fuses.

Thanks for the replies, I'll keep you informed on the progress.