Circuit for PIC18F4550 firmware

[nikhil_jain]

The firmware for PIC18F4550 is available on the link http://www.lvr.com/hidpage.htm but this works for PICDEM FS USB Demo Board.

I checked the schematics for this board as made available by Microchip but that is a generic scheme. I want to build my own circuit to test this firmware. Can you please provide me the circuit for my purpose?

Thanks

[Jan Axelson]

I think just about any circuit for this chip that has a USB connection would work.

Jan

[nikhil_jain]

yes.. but i am looking for an exact circuit to run your firmware.

i have found different circuits and i am confused now which one to use.
There's one simple circuit given on this mikroe's page at last (http://www.mikroe.com/esupport/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=158) which i guess works with their library functions.

another one is on this page (http://pwc.theclarkwebsite.com/PIC18F4550usb.php)

basically no one has explained why they have used specific components (esp. capacitors) at diff pins of pic. shall i just go for any of hese circuits?

[Jan Axelson]

yes

Jan

[nikhil_jain]

I tried the firmware with the first circuit i mentioned above, but it does not seem to work. If I use the sample library code provided by Mikroelektronika, its working perfectly fine. But not your firmware. The host is not even detecting the device. Please help.

[Jan Axelson]

Take a look at the settings in main.c for the crystal frequency and bootloader and be sure they match what you're using.

Jan