Distinguish between PA and PB external interrupts
I am trying to understand the external interrupts for the STM32F103C8. It seems that I can attach an interrupt to any of the PA or PB pins. The first 5 pins (0-4) seem to have unique IRQ handlers, whereas pins 5-9 share a handler as does 10-13. When using the shared handlers I can tell which pin generated the interrupt by inspecting the PR register. However if I assign an interrupt to PAx and to PBx, they both seem to vector to the same place and I cannot distinguish whether it came from PA or PB. Is there a way to tell or should I never assign an interrupt to the same number PA and PB pins?
Thanks.

