A possible hack is replacing the pots. For something external( with wide knob etc…)
Might be a 4 layer board, eek!
wow, some interesting comments! Be great if TE released some schematics ala Korg Monotron, but I’m sure they’d be a lot more complicated.
I’m not sure what programming language the devices are built on, but my knowledge is only front end web and maxMSP, bit of arduino.
@masterofstuff124 As you said the components are all SMD, but I just realized the EFM32 comes in a BGA package, so it is impossible to probe the pins… 
One pretty easy mod would be to have CV control over the pots, although not too sure how useful that would be if they only become active during recording.
The pads on the back are JTAG but not in the standard configuration…
@dimi3 Do you think we can get more details on those JTAG pads from TE? I have ordered an EFM32 starter kit with a J-Link programmer to try to hack into the firmware, but the connector pins are called RESET, SWDIO, SWDCLK and SW0. No idea how that corresponds to those 12 pads in the back with the symbols |- |+ etc.
The POs processor (EFM32) comes from factory with a built in USB bootloader! It is possible that TE has left that intact, since it seems to be only 32KB in size. Also, the rightmost exposed pad in the back have a strange label, a dot with a double arrow, which ressembles the USB symbol. Uhm…
1 Like
^Oooooo great find! very encouraging!
Find a way to put all the PO’s on one chip =}
That would probably be harder than finding a way of putting three chips into one PO device.
There is an “exploded” rendition on TE page that shows the internal components. From there we see that the Cirrus Logic DAC has 40 pins (10 on each side). The only one with that configuration is the CS43L22:
http://www.cirrus.com/en/products/cs43l22.html
As for the 12 pads on the back, upon further investigation they may all be related to the J-Link interface, not USB. The EFM32 has support for both SWD debug and ETM trace interfaces, and those two require 11 pins, according to fig. 4.1 on this document:
http://www.silabs.com/Support%20Documents/TechnicalDocs/AN0043.pdf
I really like your investigation, Sherlock : I don’t have the knowledge to understand half of it, but it’s really amazing to see you bring new intel post after post ^^
@punji = Grandmaster !
=^D
HACK THE PLANET!
I'm afraid we will need to take a PO apart if we want to find more... if anyone has a broken one and wish to contribute to a noble cause, please contact me.
Here is a standard USB pinout, it looks like it won’t be too difficult to determine if the pads on the PO’s correspond to these.
I’m guessing that the uncircled + and - are the battery power and ground, the circled + and - are regulated power and ground, and the _ and double arrow thing are D- and D+ Maybe???
Any recommendation for how to connect to the pads? Should we build a dock like in the Instagram photo. Or maybe solder to the ports with some leads and then make a header for a nice tight removable package.
It is hard to tell from the pic but it looks like they may be using standard 2.54mm pitch, if that is indeed the case then I’d be inclined to use a 12 way double row surface mount header then use breadboard M-F cables to rig it up, you can also buy a mini USB breakout from adafruit which might prove handy/simple.
^ That is what I intend to do with mine, plus removing the display to confirm exactly how the exposed pads are connected to the processor (unless the @ONE grants my wishes :-).