Posted on June 20, 2014 at 01:12 The ADC is initialized to continuous conversion mode. An interrupt handler with a printf function will never finish in time for the next interrupt. If you need printf, move it to main.
I don't think there is a need to read the converted value both in main and in the interrupt handler.
Use the Analog Watchdog example provided with the Std Peripheral Library as a guide for initializing everything and configuring an interrupt.
Cheers, Hal