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Hi everyone.
I am a little confused as to why hot plugging is bad. I thought that hotplugging was only an issue with devices that carry power, but wikipedia says that even hotplugging rca cables is bad. Can someone shed some light on this for me?
Last edited by Super TWiT; 06-13-2010 at 09:07 PM.
A link and quote from the relevant Wikipedia article would be helpful.
I assume you are referring to USB devices. I have heard of hotswapable hard drives, but that's usually an IT Dept. thing that most of us regular users don't get involved in. That's something I've never dealt with.
As far as I know, there is nothing wrong with hot plugging or hot swapping USB devices as long as one remembers first to shut down the device to be removed using a "safely remove" or an "umount" command. Otherwise, disconnecting a device could result in corrupting the data on the removable device if a file is actively being transferred or read at the time the device is removed.
At least, that's what gurus have told me.
I know of cases where persons who just yanked a USB device out of the computer destroyed files on the removable device. I haven't personally known of the device's being rendered unusable, just individual files.
Yeah, need some more info on what exactly it is you think is bad with hot swapping. As ^ stated, as long as the process is followed data should not be corrupted.
Quote:
but wikipedia says that even hotplugging rca cables is bad
What does that even mean? What devices are they talking about?
Yes, RCA aka phono jacks or stereo jacks were not designed to be hot plugged. It is due to the center pin i.e high signal mating before the ground (ring). It is possible to blow a speaker if the volume were turned up but should not really be a problem with low level signals like video. Ok, I've never had any video equipment fail.
Neither PS/2, RS-232 or the printer port are technically hot pluggable. I have hot plugged RS-232 and never had anything bad happen. However, one of my friends blew a PS/2 keyboard controller which I believe was due to electrostatic discharge (ESD). With IDE, SCSI, SATA the controller and hardware must be designed for hot plugging.
Power is not the only issue. You also need to protect the data signals from ESD.
I still don't understand why wouldn't you hot-plug and RCA jack? It's just a low-voltage audio signal, no power or anything.
EDIT: michaelk's post wasn't there when I started writing this!
I read about the PS/2 protocol and it says that the computer can hang if the signal is disconnected white data is going through. And I have hot-plugged PS/2 keyboards and mice before, and sometimes you have to reboot to get it to work again. But then I thought what if you just leave the keyboard/mouse alone for a minute before unplugging? And it works.
The only things I hotplug are USB devices, network cables, RCA TV A/V cables (like the ones that come with a VCR/DVD player/video game console), and ⅛" stereo jacks.
I don't hotplug PS/2 cables, RS-232 serial cables, or VGA/DVI display connectors.
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