usb mouse not functioning correctly

[anawara]

I am trying to develop a usb peripheral using the PIC16C765 microcontroller. I have bought the 16C765JW controller to be able to erase the controller's rom. compilation of the usb_mouse example was successful and also the programming of the controller. However when I plug the controller into the computer nothing happens.

I have pulled up the D- to Vusb using a 1.5K resistor.

The hex file supported by microchip is working fine but it was written using the HITECH Pic C compiler.

Any suggestions?

[dyeatman]

This is NOT the Hitech C Board! Suggest you go to the HiTech C website to resolve your problems.

[anawara]

I am aware that this is not the HiTech board. I am asking about the examples provided with the CCS Pic C compiler which I am using.

[Darren Rook]

The HEX file and code provided by CCS needs a 24MHz oscillator. What oscillator are you using?

[anawara]

I'm using a 6MHz crystal as was indicated in the schematic by Microchip. Is there any website where I can find a schematic for the CCS mouse circuit? Or should I just change the crystal and keep the same connections?

[Darren Rook]

The CCS circuit with a PIC16C7x5 is just a PIC16C765 dropped into one of CCS's Software Prototyping Boards - nothing really special. Just replace the oscillator with 24MHz.

Are you using a HEX file from CCS? If so you may get by with a 6MHz oscillator if you use the programmer to enable the H4 fuse on the PIC16C7x5. Is there a H4 fuse on this chip, I can't remember.

[anawara]

the hex file that I am using is the resulting one from the CCS compiler when it is used to compile the ex_usb_mouse.c example provided with the compiler. I only have the compiler. No prototyping board. can I send you a picture with the schematic of the circuit?[/img]

[anawara]

Any ideas? the 6 MHz crystal is not working. Does any1 have a schematic that I can use?

[anawara]

what if I change the source code to use a 6 MHz clock?

#include <16C765.h>
#device *=16
#fuses HS,NOWDT,NOPROTECT
#use delay(clock=24000000) <---- set this value to 6 MHz instead of 24?

[anawara]

I've found the solution to the problem I had. Instead of using a 24 MHz crystal. I used a 6 MHz crystal and when programming the mcu i used the H4 OSC in the fuse. This property takes the 6 MHz generated by the crystal and generates an internal 24 MHz clock.

[Darren Rook]

[anawara]

No. I am kind of new to this and I didn't understand exactly what the H4 OSC was. Thank you very much for your help. I really appreciate it