OCZ NIA teardown (pics)

[japroach]

So, a week or two ago I finally got a working OCZ Neural Impulse Actuator unit. I ordered it back in May, but there were a couple delays (headset on the first unit was DOA).

Build quality on the controller box is good. Design is sharp, but so are the edges... The headset on the other hand feels much cheaper to me, ie rubber is sloppily melted to hold the cord in place.


Anyway, on to the pics (click to enlarge):

Top of the controller case, nice logo:




Bottom of the case, four hex screws are hidden by the warranty sticker. They hold a support plate, which holds the circuit board in place:




Endcaps and circuit board removed from the case. Note that on the right endcap, there is an unused hole (second from top). If a switch were installed here, it would connect to a GPIO, so it could be used to trigger something (calibration, etc.)




Here is a view of the bottom of the PCB, you can see the aluminum support plate which all of the components connect to:




Bottom of the PCB after the support plate is removed. Note the RGB ambient glow LEDs on the top and bottom. Also note the "powered by Brainfingers" (www.brainfingers.com), which is product that is quite similar to the NIA. OCZ basically took their idea/design then optimized and marketed it. Notable differences include: much lower price, USB connection, and different headband which doesn't require conductive gel.







Top of the PCB. The USB connector is on the left, the three pin headband connector is on the right.




Close up of the left side of the PCB. If you look near the top right of the image you can see a lighter color band snaking underneath U7, U10 and then finally U14. This is the isolation gap between the power plane layers of the PCB. Medical EMG/EOG/etc devices are required to be isolated, so I'm sure a similar rule applies with the NIA. You can read up a bit on isolation here: http://www.edn.com/article/CA454635.html

Dual channel optocoupler (U10), provides a path for control signals from the right side to the left. Three channel digital isolator ADUM1300 (U7), allows data to be transmitted back from the left side of the board. Isolated DC/DC converter (U14) is used to provide the left hand side of the circuit with power (+/-5Vdc).

An optocoupler uses an LED light in combination with a photodiode to provide isolation. Whereas this iCoupler digital isolator uses magnetically coupled coils. The optocoupler requires more power (they are pulling 10mA per channel), but is cheaper.





Close up of the right side of the PCB. USB PIC18F2455 (U11) is the main controller here: 8-bit, 2k ram, 24k flash, USB full speed (12Mbit/s), running at an internal speed of 48MHz. Programming header (J5) is easily accessible, but as expected the code is read protected. However, it looks like the bootloader (0x7FF and under), is readable (see machine code). Also "Table read protect" / "Table write protect boot" config fuses, are both disabled. I'm not too experienced with PICs, but I believe this means I could replace the bootloader with one that reads and transmits all of the flash data above 0x7FF (anyone know?).

Not that I could really do anything with the code, just curious. Probably just order a new 18f2455, swap it out and play around with it a bit instead (wouldn't be anything extensive).




Initial attempt at a schematic, still a few things missing. Mostly caps and the +/-4V power supply sections. I'll upload a proper PDF schematic if anyone wants, or if I ever get the thing completed.




List of some of the identifiable ICs, along with prices: excel file


Some related patents that may be interesting (second one has some waveforms):
http://www.google.com/patents?id=lbg...BAJ&dq=5692517
http://www.google.com/patents?id=lrQ...BAJ&dq=6636763

[MyWenis]

nice...make sure you take the red pill

edit: what you gonna do w/ it?

[DuMa]

wait this shit actually works?

[tobrien]

thread and pics.

[japroach]

Originally Posted by DuMa

wait this shit actually works?

It works semi-ok, but its nowhere near as amazing as you'd think. See scriveners thread for a better functional explanation: http://www.genmay.com/showthread.php?t=796132

Originally Posted by MyWenis

nice...make sure you take the red pill

edit: what you gonna do w/ it?

Can't really think of anything interesting atm. I could directly read the headset to bypass OCZ/brainfingers software, but they've done a huge amount of work there so it wouldn't get me anything other than a pretty waveform :/.

Originally Posted by tobrien

thread and pics.

thanks

[Shad0w]

nice