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NL2TTL
- 27th April 2005, 08:06
I have programmed a 18F4550 by using the PBP2.46 compiler
Only after programming it and usingi a 20 MHZ XTAL

Windows gives this message

"USB DEVICE NOT RECOGNIZED"

My config:

- PIC BASIC PRO 2.46
- GALEP-4 Programmer
- MPASM Assembler

Is there sombody how have the 18F4550 working with windows.
(The 16C745 and 16C765 we're no problem) that's working already.

Is there sombody ho have a schematic of his wiring up from the pic

NL2TTL
- 27th April 2005, 13:08
Problem solved,

Programmer wasn't set to HS osc.

Using at this time defined in pbp

OSC 48

USING on bread board a OSC 20 MHZ programmer set to HS

FinchPJ
- 1st June 2005, 06:38
I too have the USB Device Not Recognized with the USB18 demo programs, but running on the Microchip FS USB Demo board which is set to 20 MHz - can you confirm whether you got your program working at 20 MHz or did you have to change to 48 MHz?

NL2TTL
- 1st June 2005, 07:29
No i'm using the 24 MHZ

NL2TTL
- 1st June 2005, 07:37
also i have made modifications for the osc in the include file

FinchPJ
- 2nd June 2005, 05:22
As they say, I should have RTFM more carefully - I was confused as the Microchip FS USB Demo board uses a 20 MHz xtal, so I assumed the CPU was running at 20 MHz - of course it MUST run at 48 MHz - or at least the USB must - so the 20 MHz has a divide by 5 and times by 12 = 48 MHz. I also assumed that I should use a 18F4550.HEX boot loader with Microcode Loader, but in fact have to use PLL18F4550_20_48.HEX - now that was NOT documented but Mecanique are very helpful.

So for the record, using PBP 2.46, Microcode Loader and the Microchip FS USB Demo (18F4550), I need to DEFINE OSC 48