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| Thread ID: 79837 | 2007-06-02 23:05:00 | USB Problem | B.M. (505) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 555444 | 2007-06-03 03:20:00 | I agree entirely Graham. I’m just trying to find the line between Etiquette and Necessity. :D |
B.M. (505) | ||
| 555445 | 2007-06-03 04:25:00 | IF the device needs to be dismounted before unplugging then you will get the 'safely remove hardware' tray icon. That's why it's there. It always gets me when people just rip out their flash drives and say "it doesn't matter, it's always worked for me" Printers and will not matter, it's only devices with an actual filesystem and storage space of some kind |
Agent_24 (57) | ||
| 555446 | 2007-06-05 03:57:00 | Thanks Agent_24, that solves printer query, although with the Blue Screen of death, the Canon S330 seems to remember after re-booting that there is still printing to be done. Lurks. |
Lurking (218) | ||
| 555447 | 2007-06-05 04:45:00 | You'll find that it's not the printer which "remembers"; it's the OS. That means that there is some of the print file which hadn't been sent to the printer when the printer became inaccessible. (Unless it's a very clever printer, usually a networked one with a hard disk so it can do its own spooling.) | Graham L (2) | ||
| 555448 | 2007-06-05 06:15:00 | Goto the PROPERTIES>>HARDWARE>>POLICIES on any of your drives and see if the "WRITE CACHING" is enabled on whatever device you want to unplug . The grayed-out print will tell you what you need to know . If "OPTIMIZE FOR QUICK REMOVAL" is engaged, you can plug in and out to your heart's content . If you've "OPTIMIZED FOR PERFORMANCE" then . . NO . . don't yank it out . . (the verb, not the noun) . |
SurferJoe46 (51) | ||
| 555449 | 2007-06-05 06:55:00 | I haven’t had the opportunity to enter into in-depth dialogue with this Camera yet as I was only told about the problem whilst visiting the Daughter the other day . However, I shall be checking the cord, as it’s bound to have been “Yanked Out” on many occasions . :D Interesting topic though and it appears that the correct disconnection process does not remove the 5 Volt feed, so the apparatus would still be exposed to power spikes . :confused: Hmmmmm? :cool: |
B.M. (505) | ||
| 555450 | 2007-06-05 07:06:00 | to add to what surferjoe said I've found that USB flash drives tend to default to "optimise for safe removal" meaning that as long as you dont pull it out half way through copying something you should be fine. For cameras though it would pay to check at least once to see what the setting is, and don't expect it to be remembered if you change it. If the camera's memory card or internal memory has been corrupted a reformat from the cameras menu ought to sort it out. As for the 5v thing - if the manufacturers haven't taken into account that people WILL just yank thing out they need shooting. |
dugimodo (138) | ||
| 555451 | 2007-06-05 07:22:00 | If you look at a USB "A" plug, you will see that the two outer contacts are longer than the two others . The outer contacts are the power supply ones . So power is connected before the data lines are connected, and the data lines are disconnected before the +5 and earth pins . What power spikes? The +5 is from a regulated supply . This is a "hot plugging" protocol . The devices are designed to be plugged in to or removed from "live" sockets . That's how the computer recognises that a device has been plugged in . The device powers up, and sends its ID to the CPU . If the users would just follow the instructions in the Fine Manuals . . . :groan: Of course they would have to Read The FMs . |
Graham L (2) | ||
| 555452 | 2007-06-05 07:28:00 | As for the 5v thing - if the manufacturers haven't taken into account that people WILL just yank thing out they need shooting. Not the manufacturers fault, the USB spec doesn't call for prevention against idiots and there is always a warning in the manual somewhere saying do not do it. If people want to risk ruining their devices by going against warnings and common sense then it's fully their responsibility What power spikes? The +5 is from a regulated supply. This is a "hot plugging" protocol. The devices are designed to be plugged in to or removed from "live" sockets. That's how the computer recognises that a device has been plugged in. The device powers up, and sends its ID to the CPU. it's not really the electrical connection that is a problem though, it's the filesystem on the devices usually, but maybe there are some cases where saying 'safely remove' causes the device to power down in some way also?? www.usb.org should set everyone right :D |
Agent_24 (57) | ||
| 555453 | 2007-06-05 07:42:00 | If you remove a CD-R while you are writing to it, don't expect to be able to read from it. That's because the filesystem has not been closed properly. But the disk looks OK;it hasn't been physically dameged. ;) All USB devices can be plugged in, or removed, without notice, without damaging the device. But if a device has a file system, that can be corrupted if the OS hasn't been given warning, and time to close the file system properly before the device is removed. Joe suggests that the OS can be told to keep the USB filesystem up to date at all times. I'd still use the icon. ;) |
Graham L (2) | ||
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