Post by thread:[OT]: max length on usb?

Low speed: 3 meters Full speed: 5 meters Note: that is _not_ a typo. Full speed can go _further_ than low-speed! But, you can increase this by including intermediate hubs. You can have up to 5 hubs between a device and the computer. Thus max distance is 6 * 5 = 30 meters. Don't try to stretch this numbers, it isn't likely to work very well. Bob Ammerman RAm Systems (contract development of high performance, high function, low-level software) -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> Don't try to stretch this numbers, it isn't likely to work very well. From personal experience: Just as a test, I ran several lengths of "illegal" extension cables to a USB device. Although I managed to get the command that I sent to the device through this length, I was doing this only as a stress test. The message rate was very low, certainly not video. I am certain that operating beyond the length limit will cause nothing but difficulties for a device like a web cam. There are "USB lengthening" devices available that use an intermediary media. -Robert Severson http://usbsimm.home.att.net http://www.jged.com http://www.annatechnology.com {Quote hidden}> > Bob Ammerman > RAm Systems > (contract development of high performance, high function, low-level > software) > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> Note: that is _not_ a typo. Full speed can go _further_ than low-speed! Why? -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

See http://www.usb.org/developers/usbfaq.html#cab1 John ----- Original Message ----- From: <rich+spam_OUTpiclistTakeThisOuTLCLOGIC.COM> To: <.....PICLISTKILLspam@spam@MITVMA.MIT.EDU> Sent: Wednesday, January 17, 2001 1:03 PM Subject: Re: [OT]: max length on usb? > > Note: that is _not_ a typo. Full speed can go _further_ than low-speed! > Why? > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads > > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

----- Original Message ----- From: <rich+piclistKILLspamLCLOGIC.COM> To: <.....PICLISTKILLspam.....MITVMA.MIT.EDU> Sent: Wednesday, January 17, 2001 1:03 PM Subject: Re: [OT]: max length on usb? > > Note: that is _not_ a typo. Full speed can go _further_ than low-speed! > Why? Low speed and full speed operation use two differrent signaling techniques. The idea was to make it really cheap to do low speed USB (keyboards, mice, etc.) , so the signaling is much simpler than full speed. Bob Ammerman RAm Systems (contract development of high performance, high function, low-level software) -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads