Enlightenment
The speed of my 18F4550 was frustrating me - I knew it has a 20 MHz crystal and I set the prescaler etc to do the usual divide by 5, multiply by 12 but it appeared to only run at 20 MHz. When I tried on the PICDEM-FSUSB demo board it ran at 48 MHz. I have finally twigged the difference and the explanation - I program my PICDEM board using ICD2 and the "real" board using the Microcode bootloader from Mecanique.
Of course, the requisite R of TFM states clearly that the configuration fuses are set by the bootloader program (here 20 MHz) NOT my PBP program I am loading in with its OSC 48 - so I need to use OSC 20 with the loader and of course this also explains why the USB fails - not recognised by the PC because it is not running at 48 MHz. We actually chucked away a USB plug because we concluded that it MUST be the reason for the program to fail, there being no other logical explanation - the next one worked but of course we didnt use the loader for that - Doh!
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