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Do i understand correctly?

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Member level 1
Jul 6, 2009
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I would like to use the USB function of the PIC18F4550, but no where can i find a proper explanation. People say to read the protocol on the website, but where is it exactly, and is it going to explain exactly how the usb and the host communicates, in enough detail to be able to know how to set the various bits in the datasheet USB section and then what to do after setting the bits.

Do i understand correctly, i must setup the usb device in software, install a certain driver(which i can't find) and then the usb will magically 'talk' to the computer, i still dont get how one will then send stuff to the computer, and how the computer will know to link a specific GUI to that particular PIC device?

I am really lost, and am in urgent need of help. what must i do to get it working. what to read first? i don't really understand the order in which the communications happen in order to know which bits i need to set exactly, and what to do after setting the bits. I also need to know how to program the GUI so that its is 'linked' to the USB device(PIC).


They do make USB sound so easy - but as you are finding out its anything but.

The best place to start is with Microchips examples which come with pc software so you can see a working connection.

**broken link removed**

USB is a packet type transmission. Once you set up your registers and your packet, you deliver it by writing to the appropiate register.

Your packets must conform to the specific USB protocol being implemented, but generally you recieve commands/data from the host, then return data and/or responses.

On the PC side, your machine loads a driver that interfaces with the device via the port.

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