Hi all, apologies for the post in English but I don't speak French

I have built the L2M2 board but every time I connect a Logitech PCB to E1 and E2 the Force Feedback stops working completely.  I have destroyed 4 Logitech PCBs so far!

I have measured the voltage on pin 7 (phase) of the Logitech PCB Motor Controller and it does fluctuate when I test the FFB.

Is there a way I can tap into this signal and connect to the L2M2?

Avec ou sans le suiveur en entrée sur le l2m2 ?

Sorry, I really dont understand what you mean.  Google translate isn't making any sense of your replay.  Can you write it more simply?

Don't worry. Even in French , I don't understand 

Avec ou sans l'amplificateur opérationnel monté en suiveur (celui que certains n'utilisent pas,comme Iro je crois)

In english : did you use an operational amplifier used as a buffer (voltage follower) ?

Thanks for the clarification

I followed the schematics listed at http://www.gamoover.net/tuto/l2m2-interfacer-un-ffb-et-volant-sega-model-12-avec-un-pc-ou-une-playstation-23 exactly and used the LM324 op-amp

The motor controller on the Logitech board is receiving the FFB commands but is not outputting them since I connected it to the L2M2.

Can the L2M2 use the FFB signals from the motor controller input instead of the output?

As tu branché ou débranché le L2M2 avec le volant alimenté (par l'usb ou l'alimentation) ?

As tu vérifié le bon fonctionnement de ton L2M2 avant de le connecter à ton volant ?

Pour utiliser le L2M2 sans le pont en H du volant logitech il y a pas mal de modifications à faire, et je n'ai ni le temps, ni l'envie de me pencher sur ça en ce moment.

I did not check the functioning of the L2M2 before I connected to Logitech board, my mistake really.

In a previous post you said....

'Pour ta carte logitech brulé, ne l'a jette pas. Je pense que seul le pont en H est mort, tu pourra récupérer le signal directement en sortie du microcontrolleur ST (j'ai oublié quelle patte mais on l'a retrouve vite avec un oscillo)'

Can you explain what you meant?

Oui, je me souviens avoir écris ça, mais à l'époque j'avais un logitech juste pour les tests et le temps de m'en occuper  

Tu as un oscilloscope ?

Citation de: sc00b le Jeudi 12 Septembre 2013, 18:08:38 PM
I did not check the functioning of the L2M2 before I connected to Logitech board, my mistake really.

In a previous post you said....

'Pour ta carte logitech brulé, ne l'a jette pas. Je pense que seul le pont en H est mort, tu pourra récupérer le signal directement en sortie du microcontrolleur ST (j'ai oublié quelle patte mais on l'a retrouve vite avec un oscillo)'

Can you explain what you meant?

"Do not trash your fried logitech card. Only the H Bridge (not sure about translation) is dead. You can the signal straight from the ST microcontroller - I do not know which leg, an oscilloscope helps finding it -"

I have not got an oscilloscope unfortunately :(

If I do find the pin on the ST micro-controller, can the signal be used?

I have purchased some new logitech wheels so just waiting for them to arrive.  Would be nice to be able to resurrect these broken pcbs though

I am going to check the L2M2 board first before I plug any of my new wheels into it, hopefully prevent any more blowouts

ok new logitech wheels have arrived,  I have tested all my voltages on the L2M2 PCB and they are as follows...

RV5 and RV1 = 20 V
RV2 and RV3 = 12.5 V

The CW LED correctly flashes but the CCW LED at D3 is constantly lit.  Any ideas where to start troubleshooting?

try another LM324.

Ok I have replaced LM324 and things are now working.  The CW and the CCW LEDs are responding when I try out the force feedback effects.

My final problem is that my electricity keeps on blowing, every time I plug in my L2M2 the lights in the house dim and sometimes the electricity fuse blows.

Something is obviously very wrong with the board, any suggestions where to look?