I'm new to ARM and MDK, so maybe I'm missing something. For the STM32F4xx Discovery board Blinky project, the Target Options tab has a xtal frequency of 25MHz specified. The hardware, of course, has an 8MHz xtal. I assumed (silly me!) that if I altered the options tab to match the hardware, then uV4 would be smart enough to generate a #define HSE_VALUE 8000000 to override the default (25MHz) in stm32F4xx.h. But it seems not, and, of course, all timings in the MCU are wrong. I achieved the desired result by defining it myself in the Compiler tab, but surely it isn't too much to expect uV4 to do it automatically (from the xtal value in the Target tab)?