USB Mass Storage as SxS by Guy Barwood

Overcoming the cost of SxS media (Chapter 3)
Introducing UxX.
(Created 16 May 2009: Updated 17 June 2009)
By Guy Barwood - Glass Eye View
www.xdcamexinfo.com

Latest News:

17 Jun 09: Efilms have just announced a pre-manufactured ExpressCard range for using external drives. More info here.
22 May 09: Article updated to reflect the discovery that some external drive chassis do not need 5v injected onto the USB cable as long as they are correctly powered themselves.
16 May 09: Article published

If you want to post to a forum I can and do post to, please go to this one: DVXUSER XDCAM EX FORUM At least one other forum is being massively censored to remove references to this sites pages (and who knows what other information) so I recommend you avoid that forum and stick to the one above, you simply can't trust what you read elsewhere is complete.

DISCLAIMER: While every attempt is made to provide you with accurate information, no liability is accepted in any way for your use of the information on this page. This is a clear cut case of use at own risk. The page is based on information from a wide range of unverified sources and should not be taken as gospel. Test everything for yourself to your own satisfaction prior to use in production.

Introduction

This is stage 1 of this article. I have more photos and info to add as I get the chance.

Background

If you want to learn the full background to this development you need to go back to the beginning & read the development of the XxS solutions here. This development stems from there.

Enter Deti Fliegl

On the night of 27 April 2009, I received an email from Deti Fliegl with quite an interesting development in the discovery of alternative recording solutions for the XDCAM EX cameras (EX1 & EX3). In an extension of the XxS solution, where fast high quality SDHC media in an Express Card adaptor was recognised by the cameras and usable as an alternative for genuine SxS media, Deti had been experimenting with another option.

By adapting a generic Express Card, Deti extended the USB interface of the Express Card to an external USB plug. Using this USB plug, and injecting an alternative source of power for the USB cable (the Express Card interface does not power the USB cable), he discovered that the EX1/3 would recognised & record to external USB hard drives. The same limitation applies with respect to Overcranking with this solution as for XxS as the USB interface in camera is still being used and it is assumed this is the bottleneck for what can be achieved when overcranking. A new discovery was also made however: The EX1/3 are ready to accept media up to 84GB.

How it is done

Step 1: You will need a Express Card you are willing to sacrifice for this purpose. This will form the shell of the adaptor. Deti's was a cheap generic SD card reader, mine was the more expensive but ironically internally identical Sandisk Multicard reader. Please note, not all adaptors are ready for this modification.

Once the adaptor was opened, the main PCB was removed leaving only the Express Card connector inside. Using the specifications of the Express Card connector a USB cable was cut, spliced & soldered to the Express Card connector. As the Express Card adaptor does not support the 5v USB power expected, the red power connector is not connected to the adaptor.

The inside of Deti's Express Card adaptor having been gutted & soldered to the USB cable.

This is my sacrificial Express Card Flash Card Reader

You can see here this card has two board connected to each other, all I want is that little end section, the rest is in the trash can.

Its not necessarily easy to cleanly disconnect the two boards, I tried de-soldering but all I had was wick which didn't work too well, in the end the little solder points on the large board just broke the tracks away at the solder point.

As stated, the Express Card interface can not provide the 5v power to the USB cable. This is important for two reasons:

If you plan to use a USB cable powered drive (eg an external 2.5" drive) the power for the drive usually comes from the USB cable, or
If you plan to us a USB drive with its own power source, these devices MAY still require 5v on the power wire to recognise that there is a USB device on the cable in the first place. Some chassis do, some don't. If you are happy to find and use chassis that don't then you do not need to inject the 5v into this cable, however you are still going to have to power your chassis through its DC input.

If you need/want to inject the correct 5v source back into the USB cable read on here. Deti did this by spicing the USB cable mid length, I did it by sending a second USB cable into the adaptor & connecting its ground and power (not the data lines, green & white) with the cable for the data already connected. Both solutions achieve the same purpose, an external USB plug just for adding USB power to the main USB cable.

Above is Deti's solution. One plug for data, one for power and one adaptor for the camera.

Image of my solution coming soon

There are a number of ways of powering the USB cable now. You could:

Connect the USB cable for power to a USB plug on a laptop
Connect the USB cable to an externally powered USB power source

Option 2 is the easiest. There are a lot of USB power adaptors around. Many devices use the USB interface now and require extra power. Even the iPod does this. I happened to have a charger for my old HP iPaq sitting around, which is an AC to USB power adaptor. It is the charger for the iPaq if you want to charge it when not connected to a PC. As this one can supply a full amp I also know it can easily power a 2.5" drive which often require more power than a single standard USB port can supply (half an amp).

I have both options available and with Option 1 I have a 5v car cigarette light plug power supply that I can simply power with a U30 or U60 battery from my Dolgin EX-V battery plate.

Partition the drive

Any drive you use for recording is going to have to be dedicated to this purpose. The cameras are not tolerant of multiple partitions etc It has to be a clean basic single FAT32 partition. If it isn't recognised, delete the partition & partition/format it again on your computer, that's what got my drive recognised. The camera will re-format the drive up to its maximum 84GB support offering up to 308min of recording (just over 6 hours). Don't forget that is just one slot. With two of these configurations you have up to 12 hours of HQ recording (14.3hr of SP) without swapping anything. Match that P2...

Deti's drive formatted to 84GB, offering 308min of HQ recording (it would be about 430min of SP)

My 80GB drive offered 290min of HQ recording

Here is Deti's neatly mounted in an EX3.

Field Testing

I am taking the opportunity to test this solution at a weekly Australia Rules Football competition I have each weekend throughout our Winter. This shoot is only about capturing the games for the umpires & players to review later, recording in analogue SD to DVD recorders & Archos units. There is no need or desire for a HD master capture (Sony, are you listening? This is why SD is still needed in all HD cameras! Not everyone wants HD yet). Depending on the day I may not even capture to card so I might as well test this recording reliability.

So far I have shot with it once, recording continuous for about 3 hours of HQ. Not a problem, so far the reliability has been 100%. I will update this page throughout the course of my shooting

Here is mine in my EX1. Admittedly not as neat, but just as effective

Above you can see the external hard drive unit in the middle the EX1 is recording too.

My shooting environment of the day. No problem for UxX 3 hours continuous HQ recording, not a beat missed.

Conclusion:

This solution is only in its infancy at the moment. Hopefully a fully engineered solution such as MxM/MxR will hit the market simplifying its implementation. Also, the fear of using standard hard drives should not be a concern to anyone. Simply for testing we have used these drives. There is no reason you couldn't use a 2.5" solid state drive. In fact, this is really the best option as it removes all those moving parts. Solid State drives are growing larger, faster and cheaper and already represent much better value than SxS media. Not only are they much cheaper per GB than SxS, they are even much faster. Just check this link out to learn more.

A 2.5" solid state external drive would be small to mount & consumer little power. With the high speed of these drives (see link above), the video is also instantly on a ready to edit media. Use an external USB mirrored RAID array and you have instant backup of your data.

Its a shame Sony isn't being more proactive to unofficially support alternative media for their EX (eg update the firmware to allow large capacity drives). Clearly such options only increase the value to the owner of purchasing the camera. SxS offers a great option for those willing to pay for it, but XxS & UxX offer another option for the more budget conscious. For those wanting to go to a higher end option, it is clearly the nanoFlash/FlashXDR. There are lots of media solutions for EX1/3shooters, more so than with any other camera, Sony should leverage that, it might help stem their huge losses because SxS sales don't seem to be.

Having said all this though, isn't it just time Sony add a 2.5" SATA slot to cameras to allow internal use of solid state drives such as the one above. There isn't one technical reason this can't be done.

Notes on use of

Maximum capacity of drives is 84GB so there is no use in buying drives larger, the space can not be used.