Post by thread:[PIC:] USB pins, direct access?

Is there any way to access the A end B data pins of a USB port? Just like we do with the printer port? Regards, Octavio Nogueira Tato Equipamentos Eletrônicos Ltda (11) 5506-5335 ====================================================== spam_OUTnogueiraTakeThisOuTtato.ind.br ICQ# 222558485 BASIC Step - O microcontrolador mais fácil do mercado BASCOM - O mais poderoso compilador BASIC para ATMEL http://www.tato.ind.br ProPic tools - low cost PIC programmer and emulator http://www.propic2.com ====================================================== -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email .....listservKILLspam@spam@mitvma.mit.edu with SET PICList DIGEST in the body

Do you mean to flip the pins directly from say a Visual Basic program running on a computer? If so, I believe the answer is no. Josh -- A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools. -Douglas Adams On Tue, 17 Aug 2004 03:30:51 -0300, Octavio Nogueira <nogueiraKILLspamtato.ind.br> wrote: > Is there any way to access the A end B data pins > of a USB port? Just like we do with the printer port? -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email .....listservKILLspam.....mitvma.mit.edu with SET PICList DIGEST in the body

> > Is there any way to access the A end B data pins > > of a USB port? Just like we do with the printer port? > Do you mean to flip the pins directly from say a Visual Basic program > running on a computer? If so, I believe the answer is no. Something in there knows how to. It's a sad day when a man no longer has access to his own hardware :-) RM -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email EraseMElistservspam_OUTTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body

Octavio Nogueira wrote: > Is there any way to access the A end B data pins > of a USB port? Just like we do with the printer port? You'd have to write your own device driver. If you did, it wouldn't be USB anymore as that would violate a bunch of provisions in the standard. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listservspam_OUTmitvma.mit.edu with SET PICList DIGEST in the body

> Is there any way to access the A end B data pins > of a USB port? Just like we do with the printer port? Why ever would you want to do that? It just cannot be done with standard hardware. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email @spam@listservKILLspammitvma.mit.edu with SET PICList DIGEST in the body

Even if you could manipulate the pins of a USB controller itself (which I doubt), I think you'll find that most USB cards have a USB hub chip on them, which the physical ports are connected to. USB hubs are smart devices that actually inspect the traffic before relaying it, IIRC, so simply asserting a 1 or 0 on the DATA+/- line at the controller won't accomplish anything in the end. On Tue, 17 Aug 2004 03:30:51 -0300, Octavio Nogueira <KILLspamnogueiraKILLspamtato.ind.br> wrote: {Quote hidden}> Is there any way to access the A end B data pins > of a USB port? Just like we do with the printer port? > > Regards, > > Octavio Nogueira > Tato Equipamentos Eletrônicos Ltda > (11) 5506-5335 > ====================================================== > RemoveMEnogueiraTakeThisOuTtato.ind.br ICQ# 222558485 > BASIC Step - O microcontrolador mais fácil do mercado > BASCOM - O mais poderoso compilador BASIC para ATMEL > http://www.tato.ind.br > ProPic tools - low cost PIC programmer and emulator > http://www.propic2.com > ====================================================== > > -- > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > email spamBeGonelistservspamBeGonemitvma.mit.edu with SET PICList DIGEST in the body > -- -Randy Glenn Computer Eng. and Mgt. Year IV, McMaster University Chair, McMaster IEEE Student Branch randy.glenn-at-gmail.com - glennrb-at-mcmaster.ca randy.glenn-at-computer.org - randy_glenn-at-ieee.org http://www.randyglenn.ca -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email TakeThisOuTlistservEraseMEspam_OUTmitvma.mit.edu with SET PICList DIGEST in the body

> > Is there any way to access the A end B data pins > > of a USB port? Just like we do with the printer port? > > Why ever would you want to do that? It just cannot be done with standard > hardware. An engineers gotta do what an engineers gotta do (or gotta try anyway). Consider - why would anyone want to use a perfectly good printer port for anything except driving a printer ? The idea of having a bus (potentially) capable of hundreds of Mbps under one's direct control sounds very exciting. Need there be a better reason than that? :-). RM -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email RemoveMElistservTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body

On Aug 17, 2004, at 5:21 AM, Russell McMahon wrote: >> Do you mean to flip the pins directly from say a Visual Basic program >> running on a computer? If so, I believe the answer is no. > > Something in there knows how to. Huh? It's like asking to flip the actual bits on your ide, floppy, or ethernet cable. Even if you could, it would be a really bad idea. BillW -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listservEraseME.....mitvma.mit.edu with SET PICList DIGEST in the body

Randy Glenn <EraseMEPICLISTmitvma.mit.edu> wrote: > Even if you could manipulate the pins of a USB controller itself > (which I doubt), I think you'll find that most USB cards have a > USB hub chip on them, which the physical ports are connected to. > USB hubs are smart devices that actually inspect the traffic before > relaying it, IIRC, so simply asserting a 1 or 0 on the DATA+/- line > at the controller won't accomplish anything in the end. The USB 2.0 spec requires hubs (and host controllers, and high-speed-capable devices) to support a test mode that generates a high-speed "J" state (D+ high, D- low) and another that generates a high-speed "K" state (D+ low, D- high). You could presumably use those test modes to bit-bang signals on the D+ and D- pins. -Andy P.S. Why does this have a [PIC:] tag? === Andrew Warren -- RemoveMEaiwEraseMEEraseMEcypress.com === Principal Design Engineer === Cypress Semiconductor Corporation === === Opinions expressed above do not === necessarily represent those of === Cypress Semiconductor Corporation -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email RemoveMElistservspam_OUTKILLspammitvma.mit.edu with SET PICList DIGEST in the body

Amen to that! And comming up... illegal to 'tamper' with your hardware! Geez (I think its illegal in USA to modify your X-box or something?) ----- Original Message ----- From: "Russell McMahon" > > > Is there any way to access the A end B data pins > > > of a USB port? Just like we do with the printer port? > Something in there knows how to. It's a sad day when a man no longer has > access to his own hardware :-) > RM -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email RemoveMElistservTakeThisOuTspammitvma.mit.edu with SET PICList DIGEST in the body

Couple of years back I did a USB / Parallel / I2C bridge. You can do something like that. Regards, Chetan On Tue, 17 Aug 2004 03:30:51 -0300, Octavio Nogueira <EraseMEnogueiraspamspamBeGonetato.ind.br> wrote: > Is there any way to access the A end B data pins > of a USB port? Just like we do with the printer port? > > Regards, > > Octavio Nogueira > Tato Equipamentos Eletrônicos Ltda > (11) 5506-5335 -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email RemoveMElistservKILLspammitvma.mit.edu with SET PICList DIGEST in the body