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muddy0409
- 20th May 2009, 15:26
Hi all.
Thinking about a USB project, and have a couple of general questions.
The way I understand things is this: A USB device can be designed around a PIC to do something. The PC (or Laptop) to which it will communicate has to have some sort of driver in order to tell the PC what to do with the info that comes in?
Would there be a terminal program for a PC that already has some built in USB driver so that it simply displays what comes in, in the same way as it simply communicates with RS232, or does there still need to be some custom made driver written to do that,

What I have got is a device that connects by RS232 (TTL level) and spits 20 bytes at a time to a terminal program to simply display on screen. Nothing else. The terminal keeps looking at the serial input and prints whatever it reads on screen.

Anyone know of a terminal program that does the same thing with its own driver, that looks for info on USB?

I could then rewrite the external device program on a 16C745 using USBOUT

This is necessary because fewer and fewer laptops have RS232 ports these days and I don't particularly want to have to use a USB to RS232 converter.

Hope you understand what I'm trying to say.

Regards, and as always, thanks in advance.
Peter Moritz.

www.pixtuff.net

Darrel Taylor
- 20th May 2009, 22:19
You want CDC. (Communication Device Class)
It looks just like a COM port to the computer but uses USB.

For the 16C's there are some examples in the USB folder inside the PBP folder.

I've never used the old "Low Speed" devices, but I think it would be easier with an 18F2550 or equiv, since they work with High Speed, and there are more examples available.

Have a look at this ...

USB CDC Communications for Dummies! (Squibcakes)
http://www.picbasic.co.uk/forum/showthread.php?t=5806