Posted on April 16, 2012 at 09:07In TRM STM32F4 (RM0090) it says in Chapter 4 ''PWR'', 4.1.2 ''Battery...'':
Note ''Due to the fact that the switch only sinks a limited amount of current (3 mA), the use of GPIOs PC13 to PC15 are restricted: only one I/O at a time can be used as an output, the speed has to be limited to 2 MHz with a maximum load of 30 pF and these I/Os must not be used as a current source (e.g. to drive an LED).''
I hope that this statement ''Only one I/O at a time can be used as an output'' is superseded or historical? At least in the Jan 2012 datasheet of STM32F40x, Pinning table 6, footnote 2, you only specify the 3mA condition, but NOT, that it is not allowed to use several of those pins as output.
PS: In Chapter 5, ''RCC'', 5.3.19 register description APB2LPENR Bit 10..8(ADCxLPEN):it has to say ''en''abled for Bit state 1. (I would expect at least - do not disappoint me ... now it says ''dis''abled for both bit states 0 and 1)
