bluetooth interfacing with microprocessor
I know there is a lot of going back and forth here, so be patient, but I'm still trying to figure out 100% what you're looking for.
I'm going to guess one of two things.
1. You want to plug the USB BT module from Billionton into a PC and send commands to a PIC over BT. However that would require a second BT module on the PIC board.
2. I think this is what you're looking for. You want to use a PIC16F877A or the like to send commands over your Billionton BT module to some other BT enabled device like a cell phone or maybe a Palm Pilot. In order to do this with a PIC, you'll need a UART to USB converter chip. One of the most common ones that I know of is from FTDI Chip. They make a chip part number FT232R that can recieve a UART signal from the PIC and turn it into USB to spit out at the BT module.
I'm sure if you look around you can easily find another microcontroller that has onboard USB. I don't know where you live, but I thought places like
www.digikey.com and
www.newark.com ship pretty much everywhere.
However, if I were you, I'd probably go with the PIC16F877A because there exists a huge store of knowledge about this chip amongst hobbyists and the like. Plus, I've been using them for a few years and I like 'em.
So....which one are you trying to do? 1, 2, or neither?
-Sean