Hey overover, thanks for the reminder.
Out of curiosity, how does the keyboard automatically detect the polarity?
Adam
Hi Adam,
It's not quite as Bogdan describes it: Yamaha keyboards definitely check the polarity of the connected pedals during the boot process. A Yamaha foot switch (momentary switch like FC5 and FC4) has the polarity "contact normally closed", but foot switches from other manufacturers also work, most of which have the polarity "contact normally open".
Basically, it is important to ensure that the connected foot pedals are
not pressed during the boot process. Otherwise, as mentioned many times, they may work in reverse. As mentioned, this could also happen if a pedal is plugged in after the keyboard is already switched on. (In many cases it will still work normally, but this COULD result in the described error.
)
Incidentally, I am not aware of any case where the internal electronics were destroyed by connecting pedals during operation. The pedal inputs are protected against short-circuiting of the control voltage (+5V) by appropriate protective resistors, so that nothing can normally be destroyed.
The pedal detection probably takes place after the "Boot second stage start", i.e. if the status of the internal keyboard and all internal switches are taken in. This takes place directly before the Linux kernel starts.
The current status (and thus the necessary polarity setting) of a momentary switch (e.g. on/off sustain pedal) is easy to determine (contact either closed or open). Unfortunately, I don't know how exactly the keyboards detect the status/polarity of a connected Expression pedal (e.g. FC7). In any case, there is a test routine in the internal Test program that can be used to determine whether a connected FC7 pedal supplies the correct values for "Pedal Down" (maximum position) and "Pedal Up" (minimum position).
Best regards,
Chris