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	Hi guys,=20

	I am using a pic18F4553 in a project and I am having problems with
the oscillator.=20

	I am trying to use the internal 8MHz clock PLL, prescaler etc (which
works nicely clocking at 32MHz), but when it comes to working with the
USB I am failing miserably.=20

	All of the Microchip documentation seems to contradict itself in
each section when discussing the USB clock.=20

	My question is this:- =20

	Can i use the 8MHz internal oscillator to drive the 48MHz/6MHz
needed for the on-chip USB peripheral, and if so, what settings would
you use?=20

	Here is what I am using (I have documented the config settings) =20

	(MPLab 8.83, Hi-tech C 9.65)=20

	 // 8Mhz internal oscillator producing 48MHz USB clock and 48MHz CPU
clock
      // clk src from 96MHz PLL/2, =20
      // Internal External Switch Over Mode disabled
     // Fail-Safe Clock Monitor Disabled
    // INTOSC: INTOSC+CLK0{RA6}, USB-EC=20
    // CPU No divide
    // OSC Select div by 2 {8MHz internal input}=20
 __CONFIG(1, USBPLL & IESODIS & FCMDIS & INTCLKO & CPUDIV1 &
PLLDIV2); =20
	       // USB Voltage Regulator Enabled
        // Power Up Timer Disabled
        // Brown Out Detect Disabled (2.0v)
        // Watchdog Timer Disabled (1:32768)
 __CONFIG(2, VREGEN & PWRTDIS & BORDIS & BORV20 & WDTDIS & WDTPS32K);
	      // PortB A/D disabled (digital)
       // Low Power Timer1 Osc Disabled
      // Master Clear Enable
 __CONFIG(3, PBDIGITAL & LPT1DIS & MCLREN);
	     // Disable extended instruction set (Legacy mode)=20
      // Stack Overflow Reset Disabled
      // Low Voltage Program Disabled
      // Dedicated In-Circuit Port {ICD/ICSP} Disabled
      // Background Debug Enabled
 __CONFIG(4, XINSTDIS & STVRDIS & LVPDIS & ICPORTDIS & DEBUGEN);
	      // Protect bits Unprotected
 __CONFIG(5, UNPROTECT);
 __CONFIG(6, UNPROTECT);
 __CONFIG(7, UNPROTECT);
	Many Thanks,=20

	Jim
--=20
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