basic USB protocol implementation

[arunkumar1989]

Hello everyone,
Is there any basic protocol i can follow so that i can send data through USB?
I read papers about them but none can give me a clear picture.

Something of this format:

RS232-
Idle START d0,d,d2,d3,d4,d5,d6,d7 PARITY STOP IDLE
0 1 DATA(1 byte) 1 1 1

I am able to communicate using standard rs232 protocol,but cannot do it using USB.(type data in hyperterminal and recieve it on my uC(display through ))
I figured its not as simple as just giving the initialization commands to uC and start writing/reading from TxD/RxD.

I am using AT89c51 to test my protocol. I have a freescale K60 seriees uC which has a USB controller in built,on which i plan to test my USB protocol.

Thanks in advance
Arun

 

[FvM]

Apparently you need to learn about USB basics. May be a starting point **broken link removed**

To connect with Hyperterminal, you'll need to implement a CDC device on an USB enabled microprocessor. Most microcontroller vendors have example code for it.

P.S.: USB uses in fact an UART like bit protocol (sligthly different though) on the phsysical layer. Bu that's not the protocol level you are dealing with in USB programming.

 

[arunkumar1989]

Thanks for that link.I'll read up and get back in here.

- - - Updated - - -

I did some reading but i am still confused as to where exactly to begin with the programming.If you have a sample code(or a proteus simulation) that i can look up it would help me understand it better.