Posted on May 17, 2011 at 12:21I found that if the RCC_APB2Periph_AFIO option is used in the RCC_APB2PeriphClockCmd, the GPIO_PinRemapConfig should not be used with GPIO_Remap_USART2 and GPIO_Remap_SPI1. Hence, I commented them as follows: // GPIO_...

Posted on May 17, 2011 at 12:21I found the problem. It is necessary to set the clock RCC_APB2Periph_AFIO for hardware external interrupts working.

Posted on May 17, 2011 at 12:21Not hardware problem. It looks for me to set clock, GPIO, SPI, USART2 and external interrupts together with something conflict.

Posted on May 17, 2011 at 12:21I am looking into the problem which may be in my protype board.

Posted on May 17, 2011 at 12:21I can get EXTI4 only.