PIC 16f877a and PDIUSBD12

[Hesam Kamalan]

hi,
i want to use PIC16f877a and PDIUSBSD12 (philips) for connecting PIC to computer via USB port,in my project.
in schimatic, i connected GND of my board to GND of USB connector but i don't know whether conncet VCC of board to VCC of USB port or not?
if answer is no, should i connect VCC of PDIUSBD12 to board or VCC of USB connector?
guide me please. thanks

 

[penoy_balut]

Usually devices with different power sources are connected only to common ground, consult datasheet and usb literatures (more headaches to come).

 

[kchriste]

in schematic, i connected GND of my board to GND of USB connector but i don't know whether conncet VCC of board to VCC of USB port or not?

You would only connect the board's Vcc line to the USB 5V line if you intended to power your "board" via the USB. If the board has it's own 5V power supply, then you would power the board and the PDIUSBD12 with that and NOT join the Vcc's.