Using DE2 as a USB learning tool?

What are you trying to do ? Connecting a PC through USB with a FPGA ? Sparkfun(.com) and several other webshops sell FTDI USB boards (15$) . They're easy to use and you don't actually need to know anything about the USB protocol itself . You talk to a virtual comport on the PC side, in the FPGA you programme a VHDL UART ...

However if you want to study the USB protocol by itself , that's a different story ...

yes, i'm trying to make a board that would allow me to view the characteristics of USB communication through example(debugging?). I've heard all about FTDI and everyone says that i should just use that for whatever USB related projects I have in mind. BUT, there are SO MANY projects out there that use USB. Isn't this a protocol that needs to be understood?

All philosophy/politics aside, I'd simply like to learn how to write some HDL that would allow me to use the ISP1362 on the DE2, so that i can write a driver(or not, maybe winusb coudl help me) for windows and use that to further my education of USB, by later adding switches, and the SD Card, audio etc.

The ISP1362 seems to be a bit more difficult to configure ... Have you searched the forums about this USB controller ? Doesn't seem to be as popular as the ftdi devices though ...

The FTDI chips are really easy to use !! They can do JTAG too (don't know if the ISP1362 can do that ) . And you don't need to understand the USB protocol at all ! It's almost a plug & play device .

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The FTDI chips are really easy to use !! They can do JTAG too (don't know if the ISP1362 can do that ) . And you don't need to understand the USB protocol at all ! It's almost a plug & play device .

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Thanks for the reply.

I understand that the FTDI chips allow for ease of use, and think that it's great and we're lucky to have something so cheaply available to us.

But I want to learn the USB protocol, I want to build something that log all of the actions and interactions between the host and the device, so that i could learn and understand how USB works.

It might take ages to learn, but I'd still like to try.

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The ISP1362 seems to be a bit more difficult to configure ... Have you searched the forums about this USB controller ? Doesn't seem to be as popular as the ftdi devices though ...

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Yeah, I've done a bit of searching, it seems that most topics are about getting USB working on uCLinux. I'm not sure that writting HDL for uCLinux would be the same as writting a device mode description.

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But I want to learn the USB protocol

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I feel you are more inclined towards understanding the protocol. If you work as a group, you can develop the full spec quickly than working as a single person. That said, generally i have seen people dividing the project and working in groups (host controller, master state machine (USB enumeration), protocol engine, UTMI) If you want to really study the protocol, there are some very good introductions. Some of them are

[1] USB in a nutshell

http://www.beyondlogic.org/usbnutshell/usb1.shtml

[2] USB by Don Anderson

http://www.mindshare.com/files/ebook (http://www.mindshare.com/files/ebooks)/Universal%20Serial%20Bus%20System%20Architecture.pdf

[3] USB specification

http://www.usb.org/developers/docs/