Help from electronic savvy collectors please! Hot Toys R2D2 lighting mod

Hello,

I'm trying to bypass the "touch" switch on my Hot Toys MMS408 R2D2, (Force Awakens version.) This is one where there is a hard-on/off switch beneath the head but then there's this additional "light-tap" or "touch" sensor/button on the outside for easy access, (and to avoid draining the batteries), -that alternates between two lighting modes, and off, but the default "mode" is OFF, so you have to tap it twice to engage the full desired lighting effect. Typically the light feature of R2 is powered by 3 small watch batteries. LR44...I think. But I've purchased the Soap Reactor battery adaptor and power supply so I can have long-term power provided to my figures with light-up features, and be controlled by the switch in the room. The problem with figures like this is that by default they aren't just going to turn on with the flip of one switch, which is pretty annoying.

I'd like all the lights on his head to be on at all times, (when the hard switch is on), because I'm not running this off batteries anymore, and I want him displayed in full effect in conjunction with all my display lighting. As of right now, the lights won't just come on when I turn on my Soap Reactor, I have to tap his head twice every time. The initial tap turns on R2's white "projection" or hologram lights, the 2nd tap engages all his lights, (which is what I want), then taping once more will turn him back off.

I'm no expert, but I'm guessing I need to solder something on this chip/switch, or the main chip, or re-route/jump, or disconnect specific wire(s)? Its gotta be something simple,...err, right?

Circled in red in the first pic is the touch switch, on a small chip, wired back to the main circuitry at the center circled in yellow The 2nd pic is a close-up of the back of the switch after I pulled it out of its slot.. . There's a Red, Green, and Blue wire going to this.

Any pointers would be appreciated! I'd like to do this to my new Sideshow C3PO as well! - same deal there, another "tap" to toggle it on...PLEASE let me know if any of you have done something like this or plan to? Any threads I may've missed about by-passing such "touch" or "tap" buttons? or users that I can be directed to that maybe have some experience with electrical/electronic mods?

Thank you!

Hello,

I'm interrested in exactly the same modification as you (powering the LEDs with an external power supply), so I disassembled my R2 and started to look at the circuitry.
I have a first version of a schematic below, where only the three white projector LEDs a figured for the moment. To power them on permanently, a possibility would be to solder a small strap wire between nodes N and M.
I fear it will be much more complicated for the other LEDs, since the large black integrated circuit must be involved in their flashing pattern, and there is absolutly no reference on it, so we will have to "guess" how it works...
I'll keep you informed if I find something else

Hey man, thank you for this! I had just about given up, lol, wow I really didn't think it would be that intricate, I just thought iwas pretty much bypassing a switch, didn't realize it could affect the flash pattern. keep me posted!

btw, when you say solder a strap wire between "N" and "M", where do you mean specifically I see several points labeled N and M on the circuit?

N could be any of them
M would be preferably one on the upper part of the board, not the ones on the integrated circuit ... one of the points I mistakenly marked "M" on the IC is in fact one of the leads to the speaker, but I can't figure out which one without unsoldering some wires. M is the minus coming from the battery compartment after passing through the on/off switch, we could even solder it there.

For the moment I can't see any simple solution to have all the lighting turned on automatically ... Two solutions that seem feasible:
- Run two additional thin wires alongside the ones for the power supply, leading to an external switch one would have to push twice like what is done on the touch sensor.
- Build and solder a small additional circuit board to simulate a double tap on the touch sensor each time the power is switched on
I might give a try at the second possibility, but first I have to buy an iron with a small enough tip, mine is too large

In the meantime, I will also try to draw a cleaner and more exhaustive schematic, describing the use for each pin.

So, for anyone who is interrested, here is the full schematic of the main circuitry under R2's dome
Pin 7 of the microcontroller seems unused, and I don't really know what the two "104" components are, everything else seems complete.



I'm still thinking to build the small add-on circuit I will solder to replicate two taps on the sensor at startup, it will probably imply to solder something on the blue/green/red wires to the sensor board.

And there it is
I finished my little add-on circuit. It is only one microcontroller that has been programmed to replicate the effect of two consecutive taps on the touch sensor when powered up.







You can see the result in this small video

For those who would like to do the same :
On the touch sensor board,
- blue is the positive side of the battery
- red is the negative side
- green is going back to the main board, high in normal condition.
All you have to do is pull down the green line to the negative rail twice, using an output of your microcontroller. I measured around 30mA when doing this, so I used two outputs in parallel, just to be sure...

I can provide more details if required, however I don't see any other solution that would not require a minimum of electronics knowledge and equipment.

That’s great. I would love to do the same.

However, as someone who has very little experience with electronics, I would greatly appreciate if you could explain what kind of microprocessor is required and how to program it?

Also, did you disassemble the main body of R2? I wanted to take it apart to see if I can run wires through and out of the feet so I can make him mains powered and keep it hidden but I couldn’t work out how to take him apart - didn’t want to use force for fear of breaking him.

Thanks!

buchanan said:

And there it is
I finished my little add-on circuit. It is only one microcontroller that has been programmed to replicate the effect of two consecutive taps on the touch sensor when powered up.

You can see the result in this small video

For those who would like to do the same :
On the touch sensor board,
- blue is the positive side of the battery
- red is the negative side
- green is going back to the main board, high in normal condition.
All you have to do is pull down the green line to the negative rail twice, using an output of your microcontroller. I measured around 30mA when doing this, so I used two outputs in parallel, just to be sure...

I can provide more details if required, however I don't see any other solution that would not require a minimum of electronics knowledge and equipment.

Click to expand...

I used a Microchip PIC10F322, but basically any microcontroller would do the job.
I'm using Microchip's tools to program it (Pickit 4 + MPLAB X), I know there exists other third party tools to program these microcontrollers but I have no experience with them.
You will find the .hex file here if someone wants to give a try. The link between the µC pins (Microchip designations) and the wires on the Hot Toys touch sensor board are:
VDD : blue wire
VSS : red wire
RA0 and RA1 : green wire

The thing with this kind of customisation is that it requires some -potentially high- initial investment both in time and tools, and then the subsequent unit price for each part is extremely small (the material cost for the µC, the small board and wires is less than $2).
I could certainly send preprogrammed boards to whoever is interested, however this still requires to solder wires on the Hot Toys board, this can be tricky for beginners given how tiny the board and the pin spacing is.

I didn't try to open the lower part of the body. If there is no visible sign that this part can be opened without damage, we will probably have to run the wires outside the body, as hidden as possible...

buchanan said:

I used a Microchip PIC10F322, but basically any microcontroller would do the job.
I'm using Microchip's tools to program it (Pickit 4 + MPLAB X), I know there exists other third party tools to program these microcontrollers but I have no experience with them.
You will find the .hex file here if someone wants to give a try. The link between the µC pins (Microchip designations) and the wires on the Hot Toys touch sensor board are:
VDD : blue wire
VSS : red wire
RA0 and RA1 : green wire

The thing with this kind of customisation is that it requires some -potentially high- initial investment both in time and tools, and then the subsequent unit price for each part is extremely small (the material cost for the µC, the small board and wires is less than $2).
I could certainly send preprogrammed boards to whoever is interested, however this still requires to solder wires on the Hot Toys board, this can be tricky for beginners given how tiny the board and the pin spacing is.

I didn't try to open the lower part of the body. If there is no visible sign that this part can be opened without damage, we will probably have to run the wires outside the body, as hidden as possible...

Click to expand...

Thank you very much for that. I’ll go away and see if I can work out how I could do this myself.

Otherwise I might take you up on the offer of a preprogrammed board if you’re prepared to do that. How much would you ask for one?

I guess something like 5€ + shipping ... haven't thought on any detail yet, but that should fit in a regular bubble envelope.

I was telling myself it would also be possible to make it cycle automaticaly between each position : all lights off / only projectors / all lights on, with any timing required on each step. That would make R2 more "alive"

Further mods could also be to set up independent control for the projectors : I always wondered why the middle step was "projectors on + standard lights off", and not the opposite.
One could also want to use the remote control to control the lights instead of the sound, unfortunately my R2's sound system never worked from the beginning, and I'm having a hard time to figure out what's happening with the remote control...
That would require more substantial hardware modifications though.