When I was properly informed about computers we used the parallel printer port or the serial port. Now there is the USB. Does anyone know how I can address a particular USB and make it do I/O?

 

Sure, I can make USB sing songs and do dances. What did you have in mind?

 

Does anyone know how I can address a particular USB and make it do I/O?

Maybe Jan Axelson can help you out:
http://www.lvr.com/

 

She definitely wrote a terrific pair of books. You should also check out

www.usb.org

There you will find a mountain of ".pdf" documentation. It may take upwards of several months to go through it all.

A process known as enumeration will be used to assign an address and figure out how many endpoints there are and what capabilities a function has. Among all the kinds of things you will encounter are the HID(Human Interface Device) and the Bulk Only Transport. Have fun and knock yourself out!

 

Or just use an FTDI chip, such as FT232. It connects to the USB port, can appear and be accessed as either a COM port or a USB peripheral. And outputs TTL level serial signal.

 

Gentlemen, I'm also a member of several VB6 forums where this question comes up every few weeks. I always tell the TS that if they don't have a SDK for the device they're SOL. Have I been giving them erroneous information?

EDIT: That would be a SDK for a given programming language.

 

USB has two lives, that of device, and that of host. As a host residing within a Window's environment, you require additional Window's resource capabilities, typically made up of a device driver interfacing to an enduser application. That is a field in it's own. An SDK gives on the ability to fast track that end of things. Jungo offers driver development software, but an app is still required to 'process' the data.

Luckily, Windows has a number of 'generic' drivers that will auto launch when certain USB devices 'identify' themselves in the appropriate manner. Mass storage and HID classes being common.

Using this info, your device can 'emulate' these protocols and communicate over the generic port. Windows typically launches an app that recieves the 'data' over the port driver. In the HID class for instance, you could send data that could appear in a text editor.

How usefull is this?, great for learning, but if you want to 'process' the data, you'll need an application running on the PC operating system to perform the required tasks.

 

Did ya'll hear that they're coming out with USB 3.0? Pretty neat.

 

USB has two lives,.....

Mass storage and HID classes are recognized by the OS so I'm not referring to them.

 

Mass storage and HID classes are recognized by the OS so I'm not referring to them.

well, may I add then that a class that provides for vendor extensions may be well served with an SDK?