board.getpin( ).write( ) | ArduinoMega2560 problem about pyfirmata HOT 2 OPEN

Found, problem, but not solution yet,
as there are values transfered under ANALOG MESSAGE command, like in Pin class
its write function msg = bytearray([ANALOG_MESSAGE + self.pin_number, value % 127, value >> 7])
for both, Servo and PWN pins, well on arduino mega there are 15 PWM pins, this analog message will be transmitted with pin_number more that 15, but firmata analogCallback attached function can recognize it only if pin_number is less than 15
using these PWM pins can cause problems when somebody using almost all internal Arduino Timers.
If it was on purpose then i'm just saying that all digital pins (at least on arduino mega) can be used for servo PWM generation as servo library using same internal timers

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Running into the same problem 5 years later, pretty much got exactly as far as you did. No fixes on my end, just consolidating pins which is what I should have done to begin with.

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