# Asus P4P800-P4C800 Series: How to Connect 1394/Firewire Ports



## clintfan (Sep 4, 2003)

The following is an article about connecting extra 1394 Firewire ports. Many PC cases come with front-panel Firewire connectors, so some of you may find this useful. Examples come from the Asus P4C800-E Deluxe, but it the text is not wholly specific to that mobo.

The bulk of this article deals with Firewire pinout and signal details. *In most cases your extra Firewire ports will be so easy to connect that you will not need this information.*

One caveat to all of this is that I personally don’t yet have any Firewire devices to test with. So all this data assumes that things will work properly after hookup. Everything here was learned from ohmmeter inspection of connectors, product manuals, and many often-misleading web searches. Still, I learned a lot from writing this. If anything changes after I get some Firewire, I will update this article.



PART 1: THE BASICS

In terms of *software*, not all motherboards (mobos) provide drivers for the Firewire. On the Asus P4C800-E Deluxe, the driver is provided by Microsoft during WinXP install, and no driver is available for download from Asus. Instead our focus will be on the hardware.

For *hardware*, Intel ICH5-based mobos supporting Firewire use an onboard PCI chip, such as a VIA VT6306 or VT6307; or a T.I. TSB43AB22 or TBS43AB23. The chip supports rear-panel port(s), or onboard 10-pin headers (one pin is a key), or both. The Asus P4C800-E Deluxe is an example of a mobo providing both: one of each. The MSI Neo 875P FISR2 is an example of a mobo only providing 3 headers. 

I have learned that due to prevalence of other Firewire-based devices such as internal hard drives, the mobo header usually has a standard pinout. 

_(Note for ALL diagrams: this is not “code”, just a way to get a non-proportional font. The Forum unfortunately displays the word “code” too.)_

```
10-pin                                            6 or 4-pin
mobo    <------------- cable ------------------<  Firewire
header                                            jack

              Figure 1: Typical simple hookup
```
If your front-panel connector happens to use a matching 10-pin connector as above in Figure 1 (one pin is a key), you are already in business: just plug onto the mobo header. If the cable doesn’t reach, you may be able to buy an extension (I haven’t verified this): firewire can run up to 4.5m between nodes.


```
+---------+
                                    | circuit |   4-pin
10-pin          panel             >-------------< iLink jack
mobo    <------ cable ------> or    | board   |
header                            >-------------< 6-pin
                                    |         |   Firewire jack
                                    +---------+

          Figure 2: Rear panel dual-port hookup
```
Some cases also come with supplemental rear-panel 6-pin Firewire and/or 4-pin iLink jacks as in Figure 2. These have a 10-pin keyed connector which plugs on in similar fashion. For multi-port panels, you may not have enough onboard headers to supply both ports; see the Asus detail below in Part 4 of this article for the P4C800-E Deluxe example.


```
10-pin  ?? <-------------  panel              6 or 4-pin
mobo    ??  <------------- cable ----------<  Firewire
header  ??   <-----------                     jack

          Figure 3: Hookup using individual wires
```
BUT if instead your front panel connector comes as a series of individual signal lines as alluded to in Figure 3, you will somehow need to identify which of the four to seven wires from the front panel jacks should go to which pins on the mobo header. You may do this via labeling, trusted documentation, an ohmmeter, a “beeper” light, or visual inspection. Afterward you can use the diagrams and table in the rest of this article, to make the proper connections.




PART 2: IEEE 1394 PINOUTS

The remainder of this article concerns the use of individual connector wires to connect the Firewire jacks, or whenever pinouts or signaling need to be determined.

I will start by describing the pinouts of the headers and jacks, then explain the wiring you will need to establish, in order to present the necessary standard Firewire or iLink interface at your panel.

I avoid using the terms “connector”, “male”, or “female” because I have found them to be used inconsistently around the web when describing Firewire. Instead, I am using the term “jack” to describe a port or receptacle on the PC, and “plug” to describe an external cable end which may be inserted into the jack.


```
+---------------+  Figure 4: Standard mobo 1394 header
| 2  4  6  8 10 |
|               |  Shown looking down from the top.
| 1  3  5  7  x |  (space marked “x” is the key and has no pin)
+---------------+
```
Figure 4 above shows the pinout for a standard IEEE 1394 header on the mobo. If you have an Asus P4C800-E Deluxe, MSI Neo 875P FISR2, or similar, this is how the headers will look. _(Note: pin numbering here is taken from the MSI Neo manual; the Asus manual only designates header pin 1)._





```
+---------------------------\
|                            \    Figure 5:
|                             \     IEEE 1394 Firewire jack
|     |  2  |  4  |  6  |      \
|     |     |     |     |       \   Shown looking in
|     +=====+=====+=====+        |  from the front.
|     |     |     |     |       /   (magnified for clarity)
|     |  1  |  3  |  5  |      /
|                             /
|                            /
+---------------------------/
```
Figure 5 above shows a Firewire jack. Firewire differs from iLink in that Firewire uses a 6-pin jack, because it has 2 extra pins for power and ground. The jack’s shape is pointed at one end to avoid incorrect plug insertion. 

In the center a small tongue sticks out, which has 3 electrical contacts on each side; the picture shows this tongue like "+==+==+". When the pointed jack end is at the right, odd numbered pins run along the bottom of the tongue with pin 1 at the left; even numbered pins run along the top and pin 2 is at the left. Note pins 1 and 2 are slightly longer than the others, such that power and ground will make contact with an inserted plug before the signal lines do.





```
+------+  tab  +------+
|      +-------+      |  Figure 6: iLink jack
|                     |
|  +===+===+===+===+  |  Shown looking
|  |   |   |   |   |  |  in from the front.
|  | 4 | 3 | 2 | 1 |  |  (magnified for clarity)
|                     |
|                     |
+---------------------+
```
Figure 6 above shows an iLink jack. This is a 4-pin variation of Firewire used by Sony among others. This jack’s opening is about 3 times smaller than a Firewire jack, and provides no power or ground (except the case shield). One long edge has a tab protruding into the opening to form a key to avoid incorrect plug insertion. In the center a small tongue sticks out, which has 4 electrical contacts on one side only. The picture shows this tongue like "+==+==+". When the tab is at the top, the contacts are on the bottom of the tongue, and pin 1 is at the right. 




PART 3: FIREWIRE SIGNALING

Now let’s look at the signals present on these pins. This will imply the wiring you need to create, in order to present a standard Firewire or iLink interface at your front panel jack. 

The following table lists the Firewire or iLink pins, what mobo header pin they need to attach to, and what signal is carried on each connection. Refer to the pinout diagrams above.

The table is listed by Firewire pin number, not mobo pin number. Asus signal names are also given to illustrate slight variations (from the standard) in signal naming by vendors. Wire colors are omitted from the table because the colors vary so much from unit to unit. 


```
Firewire     iLink       Mobo Header   Standard    Asus 
Pin          Pin         Pin           Signal      Signal
--------     -----       -----------   --------    ------
1                        7+8           POWER       +12V
2                        3+4+10        GND         GND
3            1           6             TPB-        TPB0-
4            2           5             TPB+        TPB0+
5            3           2             TPA-        TPA0-
6            4           1             TPA+        TPA0+

Table 1: Jack vs. header signals
```
FYI, TPA +/- are a twisted pair, which carries differential receive and transmit data. TPB +/- are another twisted pair, which carries receive strobe, and transmit data.

It does not matter which header GND pin the cable shield goes to, vs. which pin the electrical ground goes to.

Please note that the +12V power and GND ground lines may attach to *multiple header pins* for optimum grounding and current-carrying capacity. Also note the Firewire voltage is allowed to be up to 40V, depending on manufacturer (though 12V is easy to get from an ATX power supply and may therefore be commonly seen in PC’s).




PART 4: ASUS REAR PANEL HOOKUP

My Asus P4C800-E Deluxe came with a number of accessories, one being a bag labeled “C100F8-0100A” containing a PCI filler panel mounted to a small circuit board.

_(Note that Asus manuals instead show a completely different, molded 1394 jack/cable assembly, but this was not what was supplied with my kit.)

My apologies for the unusually poor picture quality here!_

```
Asus rear-panel      +-------------------------------+ 
Firewire/iLink       |HEAD1+--    --+ +--    --+HEAD2| 
Panel                |     | 123456 | | 123456 |     | 
#C100F8-0100A        |     +--------+ +--------+     | 
                     |      +------+     +----+      | 
                     |      |      |     |    |      | 
                     |      |      |     |    |      | 
+--------------------+------+------+-----+----+------+-+ 
PCI blank panel             Firewire      iLink        | 
                            jack          jack         | 

      Figure 7: Asus dual-port rear panel
```
Figure 7 above shows a top view of the circuit board and panel. Through the panel go a Firewire jack on the left and iLink jack on the right. The circuit board is labeled “1394 CON” and has one 6-pin header behind each jack. The header for Firewire is labeled “HEAD1” and the iLink header is “HEAD2”. The board also has tiny inline resistors for each signal line and the voltage line.

Tables 2 and 3 below give the pinouts for both headers on the circuit board.


```
Firewire     HEAD1         Standard    Asus 
Jack Pin     Pin           Signal      Signal
--------     -----------   --------    ------
1            1             POWER       +12V
2            2             GND         GND
3            3             TPB-        TPB0-
4            4             TPB+        TPB0+
5            5             TPA-        TPA0-
6            6             TPA+        TPA0+

Table 2: Asus circuit board Firewire pinout



iLink        HEAD2         Standard    Asus 
Jack Pin     Pin           Signal      Signal
--------     -----------   --------    ------
             1             nc          nc
             2             GND         GND
1            3             TPB-        TPB0-
2            4             TPB+        TPB0+
3            5             TPA-        TPA0-
4            6             TPA+        TPA0+

                          (nc= not connected)

Table 3: Asus circuit board iLink pinout
```


In a separate bag also came a grey 12-inch mystery cable, which I finally learned mates the Firewire panel circuit board to the mobo Firewire header. This panel cable came in a bag labeled “14-143000084”. 

```
+--------------- TPA+ ---------------------- red ------------+
|                      (twisted pair)                        |
|    +---------- TPA- ---------------------- green ----+     |
|    |                                                 |     |
|    |  +--------+---------- GND -----------------+    |     |
|    |  |        |                                |    |     |
|  +-|--|--------|-+                          +-+ /    \ +-+ |
|  | 2  4  6  8 10 |     Asus Firewire     +--+ +/------\+ +-/+
|  |    |   \ |    |     panel cable       | 1  2  3  4  5  6 | 
|  | 1  3  5| 7  x |     #14-143000084     +-|-----|--|-------+
|  +-|----/-|-|----+                         |     |  |  to
|    |    | | |                              |     |  |  filler
+----+    | | +------------- +12V -----------+     |  |  panel
 to       | |                                      |  |  HEAD1
 mobo     | |                                      |  |  or HEAD2
 header   | +--- TPB- ---------------- orange -----+  |
          |           (twisted pair)                  |
          +----- TPB+ ---------------- blue ----------+

          Figure 8: Asus rear panel attachment cable
```
Figure 8 above shows the internal wiring of the attachment cable. Connectors are shown here in top view, looking down on wires entering the back of the connector. The smaller plug at right has tabs on the rear, to engage with wide notches in the rear of a circuit board header; pins 1 are marked on the board. 



An ohmmeter confirms that the two jacks on the panel are independently wired, so if you happen to have a mobo supporting 2 external Firewire jacks, you can attach both jacks. For example, the VIA VT6306 chip supports up to 3 devices, the VT6307 up to 2. 

The Asus P4C800-E Deluxe, having a VT6307 chip, supports only 2 Firewire devices and offers only one Firewire header, “IE1394_2”. Thus you must _choose_ which of the two jacks you want to use, and plug the panel cable into the appropriate header. I recommend the larger Firewire jack, since it can supply voltage; if you ever need iLink you can get an external Firewire-to-iLink adapter cable, which drops out the extra 2 pins. It would be a good idea to put a piece of sturdy tape over the other (dead) panel jack.




REFERENCES

This link to FireWire Cable Information contains a good diagram of the iLink jack with signaling, but without the confusing male/female designations. One thing to remember about these diagrams is that the ones on the right are both looking into _jacks_, not plugs.

This Fire on the Wire article provides a good technical overview of Firewire, in particular discussions of the allowable topology, especially as it relates to use with DV (Digital Video).

And finally, PDF page 121 (manual pg. 105) of this 3-MB Silicon Graphics SG 320 Workstation manual contains a definitive diagram of the pinout of an IEEE 1394 Firewire jack. This was extremely useful, and cleared up many misunderstandings gained from the various websites.


-clintfan


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## Mental_Myopia (Oct 10, 2003)

Does VIA have any updated drivers for this?
Would installing just the INF update from the VIA 4-in-1 provide an update to it?

Great writing, and thanks for taking the time to type it all out and research!
I used the Asus and Antec directions to install my firewire, but this is a lot more clear.


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## IanRietschel (Jun 27, 2010)

Hi, I have a ASUS P4P800 SE motherboard with 4 gig of ram, and a 3.4 Ghz Hyper threaded processor. It is slow compared to new later machines of today. As this motherboard does not have a header on the board for firewire (IEEE 1394) I have installed a pci to firewire and USB card in one of my PCI slots. The band width speed on PCI is not as fast compared to PCIe or on a motherboard with a firewire header connection but I wanted to try to connect my front PC case Firewire 6 pin port to the PCI expasion card. The case came with the cable insde connected to the front port and has the wires on the end ready to go to a motherboard firewire header connection as you mention in your post. I would like to know how to connect up the wires I have in the case to the PCI Firwire expansion card which has an internal firewire 6 pin port on the card as well as two external ports of the same. The PCI firewire card came with a small 4 pin to 6 pin plug standard cable and I thought I could cut the 4 pin plug off and wire the inside case cable to it. The inside case cable hase six wires with small black plugs on each wire. They are marked as follows -

TPA+ blue wire
TPA- yellow wire
TPB+ green wire
TPB- yellow with black tracer
VG two wires one brown wire and the other wire is white with black tracer
VP white wire

Can you tell me which wire would connect to where on the 6 pin firewire plug? I would probably need an ohm meter (which I already have) to check if I have it correct.
It looks like by your diagrams and information it should be like this -

TPA+ blue wire connects to PIN 6
TPA- yellow wire connects to PIN 5
TPB+ green wire connects to PIN 4
TPB- yellow with black tracer connects to PIN 3

Would VP white wire, would that be power and would it connect to PIN 1 ???
Would VG with two wires one brown wire and the other wire is white with black tracer, would that be ground and connect to PIN 2 ???

Would this be correct?


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## Wrench97 (May 10, 2008)

Yes VP is power and VG is ground.
Power to pin 1, Ground to pin 2 

This thread is from 2003 all the original posters are long gone.
I'm going to close this one, if you need further help please start a new thread and list the brand and model on the card you purchased.


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