Cannot attach servo on some GPIOs

[ABOSTM]

Concerning issue with GPIO, I found a limitation in Servo.h that limit internal pin number used to 0..63.
But in your case, pin number PA0 is 103 and thus out of range.
I proposed a patch to extended usable pin number to 255.
See Pull Request:
https://github.com/stm32duino/Arduino_C ... /889/files

[Step73]

Good catch! I'm going to patch the library manually to check if it fixes. Thanks.

[fpiSTM]

@Step73
I've merged the fix made by @ABOSTM, here you will find the wiki made by him about the Servo:
https://github.com/stm32duino/wiki/wiki/Servo-library