LPT virtual ports

General discussions about V-USB, our firmware-only implementation of a low speed USB device on Atmel's AVR microcontrollers
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ksz
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LPT virtual ports

Post by ksz » Wed Jan 10, 2007 4:10 am

..is it possible to do such a device (USB-LPT) in system visible as additional LPT port?

christian
Objective Development
Objective Development
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Post by christian » Wed Jan 10, 2007 11:18 pm

Yes, it is possible. However, you'll need your own host-side driver. Implementing the printer device class requires at least one bulk endpoint which is not supported by low speed USB devices.

If you write your own host-side driver, you can choose a protocol based on control- and interrupt-endpoints only.

ViSoft

Re: LPT virtual ports

Post by ViSoft » Fri Feb 05, 2010 11:10 pm

Hi,

at first:
The commercially availiable USB2LPT convertors does not create another virtual LPT port in the PC, BUT HERE is something magic that is supported by the driver that creates another LPT!

at second:
Supports multiple endpoints: one control endpoint, two interrupt/bulk-in endpoints and up to 7 interrupt/bulk-out endpoints. (Bulk endpoints are forbidden for low speed devices by the USB standard.)

..This is the feature description from the V-USB mainpage at the obdev page. This means it could be possible to implement such FW that will make the AVR usable as a printer (as an inspiration see

Code: Select all

http://www.recursion.jp/avrcdc/
).
It would be wonderfull if the AVR printer could be controlled from for example the General Text Only Win32 printer driver!
I have one simple question: Is anybody able to do that? :wink:

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