How do USB-IDE cables work?

There's a chip with a pretty fancy set of digital logic in it.

Probably not. USB sends CRCs along with all of its data transfers, so it's pretty unlikely that your PC won't notice if the data does become corrupted somewhere inbetween the hard drive and the PC itself.

The better breed of USB devices has the necessary drivers and stuff right on there. The not so good ones still require you to plop in an install CD. For example the Logitech wireless mouse was true plug-and-play. No CD needed, plug in, a few mouse clicks, done. The digital camera, a whole 'nother story. Refuses to download onto a newer PC (so far).

There can be some weirdnesses though: For example when zip files are stored on my LAN drive and I want to unzip them right there and into the same directory I receive the error message "Not a ZIP File". If I copy that very file to a local HD it unzips just fine. Ok, that LAN drive runs Linux but I still don't understand why because the unzip routine runs on a Windows PC.

Must be a windows user.

Isn't it amazing that a P.E. did not notice that the USB plug has 4 pins and a IDE interface has 40 pins.

Or is there a chip hiding somewhere on

And we have another gmail loser.

donald

This would be a good Dilbert story :-)

customer: My USB device doesn't work. support: Just plug-in the device and copy the drivers. customer: But I can't do this, because my USB device is not working! support: I see. Looks like you didn't read the fine print: You need to buy an extra computer to copy the drivers!

Actually, I don't recall my Fedora Core installation requesting drivers either.

I'd thought, perhaps the USB sent the data serially using fewer pins.

I'm a chemical engineer PE, not an Electrical PE. Are you an Electrical PE?

It works, for free, on whatever machine I use. So I use it.

Thanks to everyone else for the... more useful... replies

Michael R. Darrett, P.E.

And the worse breed of operating systems will just load the drivers automatically.

This guy discovered that people will happily plug in USB flash drives found lying on the ground outside the office:

Now, programs run from a flash drive will normally only get the privileges of the user who runs them. But if you can provide your own driver, that will run with kernel privileges.

Sure, although in Windows XP "regular" users can't install drivers anyway. There's also a registry key that controls whether any unsigned driver will automatically (silently) install (not a good idea!), prompt the user to choose whether to install it or not (the default), or completely refuse to isntall it.

Not that I'm suggesting plugging in a "found" USB memory stick is a good idea.

For a well-funded operation (commercial or national espionage) it wouldn't be difficult at all to go to a store, buy a bunch of memory sticks, plant your trojans on them, re-package them and return to the store to put them back on the shelf ("unstealing"). Hmm...

Chemical engineering P.E.?

Ok, consider a manifold with 4 pipes on one side and 40 on the other. Your task is to get all 40 streams from one side through the 4 pipes on the other side without cross-contamination.

Wow, look at this. 25 pins in, two pins out. And it WORKS! It's magic, I tell you.

Michael R. Darrett, P.E.

IIRC, there are a few standard USB device classes, such as mouse, keyboard and mass storage. As long as the device identifies itself as one of these types, the OS standard drivers should work with it. No additional drivers need to be installed.

Digital cameras (for the most part) are _not_ mass storage devices and do not work with the standard USB device class drivers. They require custom drivers to be installed.

That may be due to how the Linux system maps FAT/VFAT file names from the LAN drive (an SMB device, I assume). There are many weirdnesses in how Linux/Samba handle file names and permissions. Check out the Samba man pages to see all the screwball options. From what I've heard, Microsoft has developed quite a few nearly incompatible versions of SMB in the past. Due to personnel turnover and a lack of documentation, the only decent resource for understanding how they all fit together are the people working on the Samba project.

Every digital camera I ever plugged into any PC I ever plugged one into saw it as a removable storage media device and assigned it a volume letter in windows or Linux. In fact, I can even plug one into my PSP.

A volume letter in Linux? Never seen one.

While there probably are some cheap cameras that provide a mass storage interface on a USB port, most of the higher end models that I've seen have remote control capabilities that don't map to block device I/O. Aside from that detail, many newer Linux distributions include Gphoto, which supports loadable driver modules for quite a few higher end cameras. These drivers provide support for viewing the camera's contents as a mountable file system as well as supporting other functions.

Try lsmod before and after plugging in a camera to see which drivers are loaded.

Hey, that's NOT the important part. It's possible to play an ExpressCard through four of its many pins, because those four ARE a USB2 interface. It isn't possible for IDE and USB mainly because of interface-age-and-paradigm differences that are completely invisible from outside.

USB requires intelligence and uses negotiation to determine device type, address, etc. IDE requires a classic I/O bus of the type in an IBM PC/AT (with lotsa speed and other enhancements added in as an afterthought). Thus, IDE devices are generally not programmable for USB functions. The USB/IDE adapter has a smart interface for the USB bus, which makes negotiation claims appropriate to a generic 'mass storage class' driver model and handles data transfers through USB, and another (dumb, relatively) IDE interface handled according to some IDE protocol (not necessarily a full functioned DMA133 capability, it could be VERY limited).

The USB/IDE interface has to be a small computer with two standard computer interfaces and maybe an activity LED.

whit3rd snipped-for-privacy@gmail.com posted to sci.electronics.design:

Nahh. Even a relatively small FPGA can do it easily.