Thrustmaster RCS USB Conversion

[Vortice]

Recently I managed to pick up a set of new old stock Thrustmaster RCS pedals from ebay for only £50.

 

 

 

As this was a 15 pin gameport device I needed some way of converting it to USB so I could use it with a 21st century PC. So I removed the B100K pot and gameport wiring harness and bought an Alpha B10K pot:

 

https://www.ebay.co.uk/itm/Alpha-16mm-Panel-mounted-potentiometer-pot-6mm-splined-shaft-Select-value-EV06/142298888614?ssPageName=STRK%3AMEBIDX%3AIT&var=442189097938&_trksid=p2060353.m2749.l2649

 

and Arduino Leonardo board:

 

https://www.ebay.co.uk/itm/ATMEGA32U4-AU-Pro-Micro-3-3V-8MHz-5V-16MHz-Development-I-O-Board-For-Arduino/292560475914?ssPageName=STRK%3AMEBIDX%3AIT&var=591373315157&_trksid=p2060353.m2749.l2649

 

and fitted them into the frame of the RCS:

 

 

then flashed the board with the following sketch:

 

#include <Joystick.h>

Joystick_ Joystick;

//int xAxis_ = 0;
//int yAxis_ = 0;
int zAxis_ = 0;
 

const bool initAutoSendState = true;

void setup()
{
      Joystick.begin();
  }
  
void loop(){
 
zAxis_ = analogRead(A0); 
zAxis_ = map(zAxis_,0,1023,0,1023);
 Joystick.setZAxis(zAxis_); 
 
// xAxis_ = analogRead(A1);
//  xAxis_ = map(xAxis_,0,1023,0,255);
//  Joystick.setXAxis(xAxis_);
 
//  yAxis_ = analogRead(A2);
//  yAxis_ = map(yAxis_,0,1023,0,255);
//  Joystick.setYAxis(yAxis_);

             
 delay (50);
}

 

by connecting it to my PC with a 2 metre USB to micro USB lead:

 

https://www.ebay.co.uk/itm/2M-3M-Micro-USB-Data-Sync-Charger-Cable-Lead-For-Samsung-J3-J5-A3-A5-S6-S7-Edge/383040378996?ssPageName=STRK%3AMEBIDX%3AIT&var=651655815747&_trksid=p2060353.m2749.l2649

 

So now I have a new set of rudder pedals installed into my flight frame for about £58 total cost:

 

 

No toe brakes yet, of course, but the Leonardo board has another 5 analogue axes available so the potential is there if I feel motivated enough to make some, but this will suit me just fine for now.

 

Hope this has been useful to anyone who has a set of gameport pedals that they would like to convert to USB. It really is quite a simple process and much cheaper than buying some of the very expensive modern units.

 

Happy modding everyone!

 

 

[SCG_OpticFlow]

Why did you change the original potentiometer?

[Vortice]

Apparently 10K pots are recommended for Arduinos because they give better resolution. That is my understanding from reading around the subject, so I saw no reason to go against the advice. Also I know for certain that Alpha makes high quality pots and the one that came with the pedals had no manufacturer's stamp on it. For £2.35 including delivery it seemed like a cheap form of insurance.

[Groundhog]

Hi Vortice, I have the very same pedals but have a slight problem. Stripped them down to try and rectify an annoying squeak but I was rushing a bit and forgot to take a photo of how the torsion spring interacts/sits with the 2 upper and lower bolts on the pivot. Dont suppose you have a diagram or could take a close up photo of how they look?

 

Rgds Steve

[Vortice]

On ‎6‎/‎13‎/‎2020 at 1:00 PM, Groundhog said:

Hi Vortice, I have the very same pedals but have a slight problem. Stripped them down to try and rectify an annoying squeak but I was rushing a bit and forgot to take a photo of how the torsion spring interacts/sits with the 2 upper and lower bolts on the pivot. Dont suppose you have a diagram or could take a close up photo of how they look?

 

Rgds Steve

From one to another

 

 

Hope this helps.

[Groundhog]

3 hours ago, Vortice said:

From one to another

 

 

Hope this helps.

Nice one. If you ever strip it down, on mine both the lower bolts pointing up are the same length (the longer pair) and the downward ones are the shorter ones. Haven't a clue which of ours is the correct way though ?

[Vortice]

This picture features my original set of RCS pedals (not the recently acquired ones) that I bought a very long time ago and which I may have stripped down / modified / replaced parts on over the years, or they may have just come like that originally, I simply can't remember.

 

Anyway that's how the torsion spring lines up with the bolts and they definitely do work in this configuration so I hope you manage to get yours back into full working order soon.

[Groundhog]

Yep, all sorted now thanks. A struggle to reassemble till you realise it needs bolting together before you put the 4 in that provide the resistance against the spring! Doh! Might look at replacing the 2 plastic pivot tubes with stainless tube/washer as one has snapped the ring off the top. Not bad considering bought in 1996. Don't think any other computer gear of mine is still around at that age ?

[Sokol1]

On 4/12/2020 at 5:03 PM, Vortice said:

Apparently 10K pots are recommended for Arduinos because they give better resolution. That is my understanding from reading around the subject, so I saw no reason to go against the advice. Also I know for certain that Alpha makes high quality pots and the one that came with the pedals had no manufacturer's stamp on it. For £2.35 including delivery it seemed like a cheap form of insurance.

 

At time gameport controllers use high K value for potentiometer because they use potentiometer as resistance, high value make easy match the controller physical movement angle.

 

USB controllers can use 100K, but they tend to pick more electric noise, lower values  10 - 50K pick less electric noise, but draw more current from USB power, not an issue for a single axes control.

 

But since USB controllers use potentiometer as voltage divider the ideal is that their "effective electric angle" match controller (e.g. pedal)  physical angle movement.

Unfortunately potentiometer with lower "effective electric angles" - 30 - 60º is virtually unavailable in stores, they are make for joystick and R/C industry.

 

Use a high "effective electric angle" potentiometer (e.g. the common 270º) in a few physical angle controller  - joystick pedals, typically turn 30 - 60º, limit the voltage variation send for controller and so effective axes resolution.

 

Bi-Tech 6127 series Hall Sensor has models with lower "effective electric angle".

 

E.g. 6127V1A60L.5 has 60º of "effective electric angle", indicated by "A60" in code. A 30º model is listed in datasheet, but never find one in stores.

 

 

 

[AKA_Ramstein]

that is very nice and smart!

[Groundhog]

Going about mine in a slightly different way. I have run an additional 3 core wire whilst leaving the original wire connected. Only because I have some stuff I still like to play on an XP drive I just swap over ? The new wire currently connects to a spare analog input in a BU386 that converted an F16 TQS to USB but would kind of be handy to have it's own connection. To that end, a spare Pro Micro board (from the pack I bought to convert the FLCS) will be going into a little "breakout box" and the RCS will connect to that. Reason being, I may well look at making an Autopilot panel or similar and it's handy to have the interface box easy to connect additional stuff to ? Will add a few photos as and when...Probably not the tidiest conversions ever but all working ?

[paul_leonard]

RUSBA - Realsimulator | Online Shop

[Groundhog]

7 hours ago, paul_leonard said:

RUSBA - Realsimulator | Online Shop

Yeah well, at 125 euros, I might as well get a CH Pro Pedals set on fleabay. My RCS conversion is around the £8 mark (for the pro micro and breakout box) plus a bit of time spent. And much more satisfaction in my opinion? In fact, I could have just stayed with them connected through the TQS and not cost anything, just fancied them being standalone ? 

[Groundhog]

Changed my mind yet again. Gone for just the one wire in the pedals. If I feel the need to use with my SWF22 sticks, I will put a plug on the top end of the cable. Speaking of which, was just going to use a little crimp but then remembered I have some screw in connectors so that should look nice. The left bit will fit into the breakout box and the right bit can just screw in and out as required ??

[Groundhog]

All flashed, programmed, connections tested and ready to go in the breakout box when it arrives 

[Groundhog]

Breakout boxes finally arrived from the big digital river. Fits nicely into a 65x60mm box ? 

[1Sascha]

I used to own these and they were (as far as I can remember) spectacularly good ... especially for the time period.

 

That said: You probably could've gotten the same result with much less hassle and for a fraction of the cost. I'm still using CH Pro Pedals from the same era and have them connected through a cheapo, active gameport-to-USB converter. Works like a charm and it even recognizes the toe-brake axis.

 

Not sure if it's still available, but this is the exact model I'Ve been using for years now:

 

EDIT: Just saw that this thing is now 90 Euro on Amazon.de ? IIRC I paid around 10 when I bought it back in the day... ?

 

 

Great job on going all the way with your conversion though. I wish I had the skills to pull that off myself...

 

 

 

S.

 

 

Edited February 24, 2022 by 1Sascha

[Sokol1]

6 hours ago, 1Sascha said:

 ... especially for the time period.

... gameport-to-USB converter.

 

The thing is that being a 1999-2000's thing - when the USB ports became appear in computers, this Gameport-to-USB adapter have obsolete electronics like CH sticks, with just 8 bits (256 "steeps" on axis) resolution. 

 

The DIY <$5 Arduino PRO Micro+MMjoy2 firmware give 10 bits (1024 "steeps) or 12 bits (4096), besides provide support for contacless sensor - Hall, Magnetoresistance... in analog and digital mode.  

Edited February 24, 2022 by Sokol1