How to find the base address of usb to parallel port device in Linux?

I am doing IO programming in C in Ubuntu. And I need the base address of the port to write data.

My laptop dont have a parallel port. So I bought a USB to Par开发者_C百科allel port connector. I plugged in the device and its getting detected in /dev/usb/lp0

I ran "lsusb" to see the list of devices and I can see the ID also. But how can I get the base address ? For the usual hardware parallel devices, the base address is 0x0378. this address is not getting detected while using USB to Parallel device.

Please help.

A USB parallel port doesn't have a base address - it's not a meaningful concept for USB. I'm afraid the days of doing I/O on PC hardware via in and out instructions ended a few years ago, though lots of old tutorials still survive on the web.

You can write bytes to the parallel port as a character device, and these will appear on the printer port pins. The USB adapter will expect the other end to handshake data exactly like a printer. If you want to do general I/O prototyping, you're probably better off with a simple USB microcontroller like an Arduino.

Further discussion here.

If you are still interested to use this USB-to-parallel-printer device for your own bit-banging, it's important to know that their built-in firmware always allows controlling of D0..D7, INIT (as outputs), /ERR, ONL, PE (as inputs), but never for /ACK, BUSY (inputs), /STB, /AF, /SEL (outputs) pins. And you need an 8-bit latch (e.g. 74HCT574) for catching data while strobing.

See here (https://www-user.tu-chemnitz.de/~ygu/bastelecke/PC/USB2LPT/faq#DIY) especially for possible data rates.

Accessing from software side is a bit complicated but possible, and you may have to re-structure your software and hardware for making such adapters useable. I don't know for Linux case how to access, but IMHO you don't need to write a kernel-mode driver.