Hi : )

I'm ending alpyspectrograph driver (to work with this : www.shelyak.com/produit.php?id_produit=92&id_rubrique=17 )

And ther's something I d'ont understand :
What I want : That only ONE radio button could be on.

What I'm using in code : IUFillSwitchVector(&LampSP, LampS, 3, getDeviceName(), "CALIB_LAMPS", "Calibration lamps", CALIBRATION_UNIT_TAB, IP_RW, ISR_ATMOST1, 0, IPS_IDLE);

But ISR_ATMOST1 dosen't work... I can choose another and the first clicked is always on... What do I miss ?

Maybe try ISR_1OFMANY...and you may need to update the state of the switch with IUUpdateSwitch

As Jon said! Do you have the code for your driver hosted somewhere so we can take a look at it?

EDIT: Is it this one? github.com/indilib/indi/tree/master/3rdparty/indi-shelyak

this one (just pushed.)
github.com/djibb/indi/tree/master/3rdparty/indi-shelyak