Installing front USB cables? Help please - don't know which cables!!!


D

David D

I don't want to fry my motherboard so I thought I would ask here
first. I want to install the frontside USB slots to my motherboard.
Now, I have two sets of cables coming from the front of my case.
My motherboard is an ASUS M2NPV-VM.
The cables are multicoloured and break into four smaller pieces
labelled as such :

L-IN
L-OUT
GND
MIC BIAS

The second set, attached directly to the first is the opposite :
R-IN
R-OUT
GND
MIC BIAS

Now, I am assuming this is the cable for the headphones in the front
(located beside the USB slots)

Here is the other cable coming out of the front of the case:

DATA+1
DATA-1
GND1
VCC1

and conversely the second set of cables:

DATA+2
DATA-2
GND2
VCC2

Now I am unsure of the order of these smaller single pin female
cables. I have an 8 pin male connector on the motherboard
called :USB50 and USB70.
Since they are 8 pin male and there are 4 single pin females to go in,
I am not sure of the
1) ORDER they are put in
2) Where exactly on the motherboard it should go, although I am
assuming the USB 50 or USB 70
3) if I have the right cables from the front of the case.

I have gone over the instruction manual and it doesn't seem to help me
much.
Any help would be greatly appreciated, hopefully I have included
enough information...
 
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P

Paul

David said:
I don't want to fry my motherboard so I thought I would ask here
first. I want to install the frontside USB slots to my motherboard.
Now, I have two sets of cables coming from the front of my case.
My motherboard is an ASUS M2NPV-VM.
The cables are multicoloured and break into four smaller pieces
labelled as such :

L-IN
L-OUT
GND
MIC BIAS

The second set, attached directly to the first is the opposite :
R-IN
R-OUT
GND
MIC BIAS

Now, I am assuming this is the cable for the headphones in the front
(located beside the USB slots)

Here is the other cable coming out of the front of the case:

DATA+1
DATA-1
GND1
VCC1

and conversely the second set of cables:

DATA+2
DATA-2
GND2
VCC2

Now I am unsure of the order of these smaller single pin female
cables. I have an 8 pin male connector on the motherboard
called :USB50 and USB70.
Since they are 8 pin male and there are 4 single pin females to go in,
I am not sure of the
1) ORDER they are put in
2) Where exactly on the motherboard it should go, although I am
assuming the USB 50 or USB 70
3) if I have the right cables from the front of the case.

I have gone over the instruction manual and it doesn't seem to help me
much.
Any help would be greatly appreciated, hopefully I have included
enough information...

The first set, do have something to do with front audio. But perhaps you
have a typo here ? I would have expected to see a microphone input
instead of two "MIC BIAS" pins. L-IN/L-OUT is suitable for
traditional AC_97, and because your HDaudio CODEC has plenty of
channels on it, it no longer needs the L-OUT (or R-out) signals.
Only five wires minimum will be used. The second GND may be
redundant, and both the headphone and microphone jacks may be
able to get their GND from just the one wire.
L-IN
L-OUT
GND
MIC BIAS
R-IN
R-OUT
GND
MIC BIAS

These signals go to the microphone jack. Corresponding
to tip, ring, and the sleeve contact respectively.

MIC-IN
MIC-BIAS
GND

For the headphone jack, the signals would be as listed here.
Again, the order I list them, corresponds to tip, ring, and
sleeve of the audio device plugged in.

L-IN
R-IN
GND

The GND can be common between the two jacks (i.e. the two
jacks share the same ground signal). Although sometimes you
can find audio wiring that has a GND for each jack (case
manufacturer too lazy to connect them on the front panel).
The Asus motherboard only has one GND, so I hope the extra
GND wire is redundant, and the GNDs on the computer case
are already joined at the case.

The L-OUT and R-OUT cannot be used, because an HDAUDIO header
uses the pins for a sense function. So only two of the four
wires can be used. And in case their naming convention is
different than the way I'm thinking, you will use either the
L-OUT/R-OUT pair or the L-IN/R-IN pair. My best guess is it
would be L-IN/R-IN. No harm if you connect either pair of
wires to the motherboard - only one pair will work properly.

So this is what the Asus header looks like, with your wiring
connected. If you really need the second ground wire to be
connected, you'll have to find a second ground pin to use.
Chances are, the jacks will work, if only one of the GND wires
is connected. If your headphones don't work with the wiring
as shown, disconnect L-IN/R-IN and try L-OUT/R-OUT in their
place. Unused wires can be left dangling. NC means "no connect".

MIC-IN ----- MIC2 X X AGND --- GND
MIC-BIAS --- MICPWR X X NC
L-IN ------- Line_Out_R X X NC
NC X
R-IN ------- Line_Out_L X X NC

The 1x4 for USB, would go on one side of an Asus USB header.
DATA+1
DATA-1
GND1
VCC1

Note that the order you list them, is not suitable for
direct connection to the Asus header. You can see a
typical dual USB header here. A 1x4 connector fits to
either side of the header. And the order of the pins
is usually VCC, D-, D+, GND as far as pin order goes.

/ vcc X X vcc \
USB _/ data- X X data- \_ USB
#1 \ data+ X X data+ / #2
\ gnd X X gnd /
X NC

Is your USB cable, a cable with four individual wires
and plastic squares on the ends ? Or is it a 1x4, where
the pin order is as you list them ? Whatever it happens
to be, the pins should line up as shown with the Asus manual,
and my drawing above is just another way to show the same
info. If the signal order really is wrong, you'll have
to fix it. This figure shows how to back a wire out of
a plastic shell, and move it to a new position. I do
these with an X-Acto knife, with the slim triangular blade.

http://www.frontx.com/head_con.html

Paul
 
D

David D

I dont; really care about the audio so much, if I can do something
after the USB I will, but for now it is fine to leave it.
The first set, do have something to do with front audio. But perhaps you
have a typo here ? I would have expected to see a microphone input
instead of two "MIC BIAS" pins. L-IN/L-OUT is suitable for
traditional AC_97, and because your HDaudio CODEC has plenty of
channels on it, it no longer needs the L-OUT (or R-out) signals.

Nope, that is as is listed.
The 1x4 for USB, would go on one side of an Asus USB header.
my mistake, it does go - VCC1, DATA-, DATA+1 GND1

Note that the order you list them, is not suitable for
direct connection to the Asus header. You can see a
typical dual USB header here. A 1x4 connector fits to
either side of the header. And the order of the pins
is usually VCC, D-, D+, GND as far as pin order goes.

/ vcc X X vcc \
USB _/ data- X X data- \_ USB
#1 \ data+ X X data+ / #2
\ gnd X X gnd /
X NC

Is your USB cable, a cable with four individual wires
and plastic squares on the ends ?

4 individuals.


Or is it a 1x4, where
the pin order is as you list them ? Whatever it happens
to be, the pins should line up as shown with the Asus manual,

Problem is the manual does not show any closeups of the USB hub in the
motherboard.
and my drawing above is just another way to show the same
info. If the signal order really is wrong, you'll have
to fix it.

Now, the male ends on the motherboard are 2 banks X4 of male
connectors. Does it matter if I pick the upper or lower bank? Will
my motherboard die if I put the pins in the wrong tip?
 
P

Paul

David said:
I dont; really care about the audio so much, if I can do something
after the USB I will, but for now it is fine to leave it.


Nope, that is as is listed.

OK, you have three options for the audio:

1) Forget about connecting it up.
2) Buy and install a 5 1/4" drive bay set of audio jacks. Even if
you do this, you'd still have to pull the return wires from the
2x5 plastic shell on the end of the wires coming from the drive
bay. Because with an HDaudio header, there is no place for return
wires.
3) Get a multimeter. Set if on the ohms scale. Plug a male to male
1/8" stereo extender cable, into the front of your computer case.
Use the multimeter to buzz from a labeled wire, to a contact on
the 1/8" plug. By doing that, you can identify which wire is
which, and tell the difference between MIC-IN and MIC-BIAS.
You can actually safely swap MIC-IN and MIC-BIAS, so you could
experiment with your two MIC-BIAS wires, and try them both
ways. One way is going to give you more microphone channels
than the other way. But seeing how screwy your audio wiring
cable assembly is, I'd really want to verify the whole
thing.
my mistake, it does go - VCC1, DATA-, DATA+1 GND1



4 individuals.


Or is it a 1x4, where

Problem is the manual does not show any closeups of the USB hub in the
motherboard.


Now, the male ends on the motherboard are 2 banks X4 of male
connectors. Does it matter if I pick the upper or lower bank? Will
my motherboard die if I put the pins in the wrong tip?

You can select either side of the 2x5 header, to make connections
with your 1x4 shell. Just make sure the VCC end is connected to
the VCC pin. If you accidentally flipped the 1x4 by 180 degrees,
you would fry whatever USB device is plugged into the port (and
maybe even the motherboard's USB interface). So take a few moments
to verify you have it the right way round. The "odd pin" should
help you identify which way round it goes.

The most safe way to deal with front panel wiring, is to not use
it at all. I actually ripped the front cable harness out of my
last build - I've taken the time to buzz and verify the wiring
on several Antec cases, and found wiring errors, so it is just
faster for me to tear it out and not be reminded by a clump of
unused cables hanging down :) The connectors on the back of the
computer, are safer in that respect, in that they are permanently
wired by the motherboard designer. Chances are, someone checked
them for correctness, before the board shipped.

Paul
 
D

David D

Ok, my bad - hard to see in the case. There are 2 banks - 4 male
pines / 5 males pins. The only info it gives me is USB78 (another
misquote). I don't know where to put the VCC from adam on this one.
 
P

Paul

David said:
Ok, my bad - hard to see in the case. There are 2 banks - 4 male
pines / 5 males pins. The only info it gives me is USB78 (another
misquote). I don't know where to put the VCC from adam on this one.

If you refer to this diagram, this is looking down at the male
header on the motherboard.

/ vcc X X vcc \
USB _/ data- X X data- \_ USB
#1 \ data+ X X data+ / #2
\ gnd X X gnd /
X NC

The header is a 2x5 pattern, and one pin is missing. The missing
pin is a key, to help you orient the cable from the computer
case.

The "odd man out" pin is on the opposite end
from where VCC goes. I.e. If you were to put
the cable on the right hand side of this diagram,
the "NC" pin would not be connected to anything.
The other four would be connected.

In this example here, the "red" wire goes to the
VCC pin. The "black" wire is GND. So the "red" wire
stays far away from the NC pin.

http://www.frontx.com/cpx101_2.html

HTH,
Paul
 
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