[Tech] Self-made Motorola Factory USB Cable

[Epsylon3]

Ok, today ive made some electronics to test different configurations of usb cables.

I can now confirm how to make a factory usb cable which allow to boot the Defy (and the Atrix too) without battery inside.

My little circuitry look like complicated because it was made to test different configurations...

You can buy these cheap micro usb connectors on ebay...

Also this cable put the Defy in a working "eth" mode, i still don't know exactly why... i was expecting a serial mode.

Bus 004 Device 007: ID 22b8:41d4 Motorola PCS 
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            2 Communications
  bDeviceSubClass         2 Abstract (modem)
  bDeviceProtocol         0 None
  bMaxPacketSize0        64
  idVendor           0x22b8 Motorola PCS
  idProduct          0x41d4 
  bcdDevice            2.16
  iManufacturer           1 Motorola
  iProduct                2 MB525
  iSerial                 3 016084D31101D002
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           39
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          4 Motorola Config 13
    bmAttributes         0xc0
      Self Powered
    MaxPower              500mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           3
      bInterfaceClass         2 Communications
      bInterfaceSubClass     10 Mobile Direct Line
      bInterfaceProtocol      1 
      iInterface              7 Motorola Networking Interface
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x83  EP 3 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x03  EP 3 OUT
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0000  1x 0 bytes
        bInterval               1
Device Qualifier (for other device speed):
  bLength                10
  bDescriptorType         6
  bcdUSB               2.00
  bDeviceClass            2 Communications
  bDeviceSubClass         2 Abstract (modem)
  bDeviceProtocol         0 None
  bMaxPacketSize0        64
  bNumConfigurations      1
Device Status:     0x0000
  (Bus Powered)

 

[mr.han]

Also this cable put the Defy in a working "eth" mode, i still don't know exactly why... i was expecting a serial mode.

"eth" ? Like at Linux Ethernet devices ? In Windows Moto adds to device manager like another ethernet device or something ? Mayby there is way to flash the phone somehow via ethernet ? or enter it to fastboot

 

[Epsylon3]

"eth" ? Like at Linux Ethernet devices ? In Windows Moto adds to device manager like another ethernet device or something ? Mayby there is way to flash the phone somehow via ethernet ? or enter it to fastboot

no, this mode is set on android by usbd, like moto portal...

but unlike the normal mode, this interface is not multiplexed... on windows it also detect the phone as a USB Modem... weird

 

[mr.han]

no, this mode is set on android by usbd, like moto portal...

but unlike the normal mode, this interface is not multiplexed... on windows it also detect the phone as a USB Modem... weird

Mayby now You can enter to fastboot and we don't know about it xD How about simply reboot phone from adb with "reboot bootloader" and try ? I know this is stupid but You can try

 

[eiyee]

Tests with factory cable

Some results from playing with the cable on defy+:

In bootloader mode, RSDlite output changes to "S Flash OMAP3630h". USB device ID stays the same, it is always 0x4280 no matter the cable.

No apparent change in recovery.

After boot with the factory cable, USB device ID in the running system changes to 0x41d4 and USB does not seem to work from within Android - but I did not check in detail. Linux system sees device as Epsylon3 showed.

---------- Post added at 02:46 AM ---------- Previous post was at 02:42 AM ----------

Also this cable put the Defy in a working "eth" mode, i still don't know exactly why... i was expecting a serial mode.

This creats a ttyUSB0. It might need a different driver (there was something about usb serial vs usb acm). No output or response on quick check.

# modprobe usbserial vendor=0x22b8 product=0x41d4
[794650.575562] usbserial_generic 1-1.2:1.0: generic converter detected
[794650.575760] usb 1-1.2: generic converter now attached to ttyUSB0

 

[Le_Poilu]

Hi

This is nice.

Little question: Can we expect using this for plugging in the device even with a battery inside, so we can have the Defy "in charge" without using the battery (sort of bypass).

My concerne is about the overheat of the battery when you use the phone on charge, in example: car mode with navigation. When battery temperature is over 42°C it stop charging, which can append quickly.. then your Defy will loss charge even if it's plugged.

 

[marhensa]

Hi

This is nice.

Little question: Can we expect using this for plugging in the device even with a battery inside, so we can have the Defy "in charge" without using the battery (sort of bypass).

My concerne is about the overheat of the battery when you use the phone on charge, in example: car mode with navigation. When battery temperature is over 42°C it stop charging, which can append quickly.. then your Defy will loss charge even if it's plugged.

+1 for this question..

Sent from XDA-Developers Android Application​

 

[eiyee]

no charging

Hi,

This is nice.

Little question: Can we expect using this for plugging in the device even with a battery inside, so we can have the Defy "in charge" without using the battery (sort of bypass).

This from a quick test:

When I connect the factory cable to running phone with battery inside (87% charged), white LED lights up, but no charging indicator in Android.

I left the phone in this state for about 10 minutes, then played some games for a little while and battery percentage stayed at 87%.

So maybe the answer is yes It can power the defy bypassing the battery but does not seem to charge the battery.

But I would watch the phone carefully! I'm not sure it is safe for the battery. (Thinking maybe it does get some power even if no charge shown and direct +5v from USB would be too much for it.)

 

[Le_Poilu]

Good if it doesn't charge the battery
This mean that it completely bypass it, and only power the phone.
So the phone is powered independently of the battery, this one will not overheat... and it I'll allow to use the defy on a long run for car navigation without discharge when the battery overheat.

 

[hackergnome]

Hi

This is nice.

Little question: Can we expect using this for plugging in the device even with a battery inside, so we can have the Defy "in charge" without using the battery (sort of bypass).

My concerne is about the overheat of the battery when you use the phone on charge, in example: car mode with navigation. When battery temperature is over 42°C it stop charging, which can append quickly.. then your Defy will loss charge even if it's plugged.

there are reports tgat using this with battery kill the battery...

Sent from my MB525 using xda premium

 

[eiyee]

Hi nogoodusername,

there are reports tgat using this with battery kill the battery...

That would be good to know!!

Could you link to the reports?

I can try to measure if there is power on the battery connectors. I noticed no degradation but only tried for some tens of minutes.

 

[hackergnome]

Hi nogoodusername,



That would be good to know!!

Could you link to the reports?

I can try to measure if there is power on the battery connectors. I noticed no degradation but only tried for some tens of minutes.

I read it on Raze Forum.... wait ill see if can give u the link...

Sent from my MB525 using xda premium

 

[eiyee]

I can try to measure if there is power on the battery connectors. I noticed no degradation but only tried for some tens of minutes.

I did a few measurements today.

With factory cable and no battery:
Between v- and v+ there is 0.1v
Between v- and a there is 2.76v
Between v- and b there is 2.76v
Between a and v+ there is -2.6v
Between b and v+ there is -2.6v

On the battery (not inserted in the phone), I measure
Between v- and v+ there is 3.95v
Between v- and a there is 0v
Between v- and b there is 0v
Between a and v+ there is 3.95v
Between b and v+ there is 3.33v

I am no electrical engineer, so not confident to interpret the results. Basically v- and v+ seem ok to me, but I have no clue about the function of pins I called "a" and "b" above, and they have opposite voltages against v+ which is might be bad.

Anyone here who knows what this means for battery safety?

 

[7_michel]

Measurements of the battrey contacts on the phone side are meaning less without any battery connected, because the phone is not active.
I made similar analysis on my HTC desire battery, results are given here: http://78michel.unblog.fr/htc-desire-battery-shutdown-analysis/
The two extra contacts ( a and b on your photo) are normally a connexion to a temperature sensistive component to record battrery internal temperature , and a connexion to the data bus of the IC located in the battery package

 

[DJ_Synergy]

i just wonder if and how we can use the "eth"-mode of this cable ...
this enters the phone into a serial mode with USB to Serial ??? can we use it to get some terminal or even flash the phone / bootloader ??? or is this just a modem connection for AT-Commands ???

 

[m11kkaa]

Is it possible, that original Moto Factory-Cables have an resistor between +5V and defy? I'm asking this because the defy gets a little bit hot when using an self-made cable.

Maybe that's just because USB has 5V and battery normally 3.3V.

 

[hackergnome]

Is it possible, that original Moto Factory-Cables have an resistor between +5V and defy? I'm asking this because the defy gets a little bit hot when using an self-made cable.

Maybe that's just because USB has 5V and battery normally 3.3V.

Do not keep battery in when using factory cable... Harmful for Defy also no stock does not have any resistor... ive torn apart the cable covers also the usb cover/case

Sent from my ME525 using xda premium

 

[Largo LaGrande]

There is no need to use such a self made usb cable for running defy without battery. Simply remove battery while booting, shortly after the blue led turns into red.

 

[TheBirdOfHermes]

Very nice and unique!

 

[hackergnome]

There is no need to use such a self made usb cable for running defy without battery. Simply remove battery while booting, shortly after the blue led turns into red.

This is used to flash your phone in BL, when you have low battery and BL says "Cannot Program"

Sent from my MB526 using xda premium