i have a black motorola v3 and so does my friend. i attached my phone and it is detected by all the mobile software i.e. p2kcommander, p2ktools, midway etc., but wen i connect his phone nothing happens, i get a pop up saying "one of the usb devices attached to this computer has malfunctioned, and Windows does not recognise it". Can this be solved?
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mikekay10 Posts: 2958
Service Provider: Vodafone
Fri Jun 30, 2006 3:48 pm
Sounds like a problem with the usb connector - I had the same issue with my first V3. Does it still charge ok?
tuff gong Posts: 9
Phone Model: Motorola RazR
Service Provider: Digicel
Fri Jun 30, 2006 3:55 pm
yeah the phone still charges ok.
mikekay10 Posts: 2958
Service Provider: Vodafone
Fri Jun 30, 2006 3:57 pm
Still leaning towards phone hardware to be honest - could be an issue with pin x
tuff gong Posts: 9
Phone Model: Motorola RazR
Service Provider: Digicel
Fri Jun 30, 2006 3:59 pm
what is pin x
mikekay10 Posts: 2958
Service Provider: Vodafone
Fri Jun 30, 2006 4:15 pm
BY krhainos:
Not sure if someone had already figured this out, but here it is..
The Motorola RAZR V3-series phones, as you all know have a miniUSB port right on the side of the chasis -- which is used for wallcharger, PC USB Modem/Syncing and for a wired headset.
First, simply throwing 5v and gnd across pins 1 and 4 does NOT put the phone in Charge mode. For this reason, the RAZR V3 is incompatible with the BoxWave VersaCharger and many other USB-based power sources.
The phone enters Charge mode in the ONLY two following circumstances :
a) Wallcharger. (duh)
b) Plugged into PC, with Motorola USB Modem driver installed, and modem is in Idle -- it can either be in Modem mode or Trickle-Charge mode -- not both simultaneously.
The phone uses Pin X, 2, and 3 as control and switches modes as necessary. The wallcharger has 5v+ on Pin 1. 3.3v+ on Pin 2, 3, and X. And Pin 4 is ground along with the metal shroud around the USB port. The wallcharger has no IC or logic inside it, just merely a 5v+ and ground wires leading to the connector -- so whatever Magic(TM) is happening on pins 2, 3, and X are happening inside the connector. Meaning, the phone sees 3.3v on pins 2,3, and X and goes "Oh, you're a wallcharger -- go to wallcharger mode" -- and if it sees nothing on pin X and USB traffic on 2 and 3, it goes "Oh, you're a computer, switch to USB mode" (and then go to trickle-charge mode when idle)
After tearing the connector apart, my theory turned out to be correct.
http://krhainos.tk/motoplug -- included are photos of the torn apart connector, and a simple 3M Sticky Note(TM) schematic.
Materials required to reproduce a REAL USB charge cable for the RAZR:
1x 200kOhm resistor
1x miniUSB cable
... that's it. really.
the trick here is the USB cable, since Pin X isn't part of the USB standard, yet Motorola uses it as a control pin to see what device is attached. Any off-the-shelf miniUSB cable you purchase is likely to not have this pin or wire running through it, so you may have to put a miniUSB male to miniUSB male cable and then gut it, just to get Pin X.
mentat6059 Posts: 1
Fri Jul 28, 2006 10:01 pm
can you repost the pictures and the schematic to the EMU plug
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