text: #ifdef STM32F4
    #include "stm32f4xx_hal_gpio_ex.h"
  #else
    #include "stm32f2xx_hal_gpio_ex.h"
  #endif
  
  // Common GPIO initialization
  void common_init_gpio(void){
    // TODO: Is this block actually doing something???
    // pull low to hold ESP in reset??
    // enable OTG out tied to ground
    GPIOA->ODR = 0;
    GPIOB->ODR = 0;
    GPIOA->PUPDR = 0;
    GPIOB->AFR[0] = 0;
    GPIOB->AFR[1] = 0;
  
    // C2: Voltage sense line
    set_gpio_mode(GPIOC, 2, MODE_ANALOG);
  
    // A11,A12: USB
    set_gpio_alternate(GPIOA, 11, GPIO_AF10_OTG_FS);
    set_gpio_alternate(GPIOA, 12, GPIO_AF10_OTG_FS);
    GPIOA->OSPEEDR = GPIO_OSPEEDER_OSPEEDR11 | GPIO_OSPEEDER_OSPEEDR12;
  
    // A9,A10: USART 1 for talking to the ESP / GPS
    set_gpio_alternate(GPIOA, 9, GPIO_AF7_USART1);
    set_gpio_alternate(GPIOA, 10, GPIO_AF7_USART1);
  
     // B8,B9: CAN 1
    #ifdef STM32F4
      set_gpio_alternate(GPIOB, 8, GPIO_AF8_CAN1);
      set_gpio_alternate(GPIOB, 9, GPIO_AF8_CAN1);
    #else
      set_gpio_alternate(GPIOB, 8, GPIO_AF9_CAN1);
      set_gpio_alternate(GPIOB, 9, GPIO_AF9_CAN1);
    #endif
  }
  
  // Peripheral initialization
  void peripherals_init(void){
    // enable GPIOB, UART2, CAN, USB clock
    RCC->AHB1ENR |= RCC_AHB1ENR_GPIOAEN;
    RCC->AHB1ENR |= RCC_AHB1ENR_GPIOBEN;
    RCC->AHB1ENR |= RCC_AHB1ENR_GPIOCEN;
    RCC->AHB1ENR |= RCC_AHB1ENR_GPIODEN;
  
    RCC->AHB1ENR |= RCC_AHB1ENR_DMA2EN;
    RCC->APB1ENR |= RCC_APB1ENR_USART2EN;
    RCC->APB1ENR |= RCC_APB1ENR_USART3EN;
    #ifdef PANDA
      RCC->APB1ENR |= RCC_APB1ENR_UART5EN;
    #endif
    RCC->APB1ENR |= RCC_APB1ENR_CAN1EN;
    RCC->APB1ENR |= RCC_APB1ENR_CAN2EN;
    #ifdef CAN3
      RCC->APB1ENR |= RCC_APB1ENR_CAN3EN;
    #endif
    RCC->APB1ENR |= RCC_APB1ENR_DACEN;
    RCC->APB1ENR |= RCC_APB1ENR_TIM2EN;  // main counter
    RCC->APB1ENR |= RCC_APB1ENR_TIM3EN;  // slow loop and pedal
    RCC->APB1ENR |= RCC_APB1ENR_TIM4EN;  // gmlan_alt
    //RCC->APB1ENR |= RCC_APB1ENR_TIM5EN;
    //RCC->APB1ENR |= RCC_APB1ENR_TIM6EN;
    RCC->APB2ENR |= RCC_APB2ENR_USART1EN;
    RCC->AHB2ENR |= RCC_AHB2ENR_OTGFSEN;
    //RCC->APB2ENR |= RCC_APB2ENR_TIM1EN;
    RCC->APB2ENR |= RCC_APB2ENR_ADC1EN;
    RCC->APB2ENR |= RCC_APB2ENR_SPI1EN;
    RCC->APB2ENR |= RCC_APB2ENR_SYSCFGEN;
  }
  
  // Detection with internal pullup
  #define PULL_EFFECTIVE_DELAY 10
  bool detect_with_pull(GPIO_TypeDef *GPIO, int pin, int mode) {
    set_gpio_mode(GPIO, pin, MODE_INPUT);
    set_gpio_pullup(GPIO, pin, mode);
    for (volatile int i=0; i<PULL_EFFECTIVE_DELAY; i++);
    bool ret = get_gpio_input(GPIO, pin);
    set_gpio_pullup(GPIO, pin, PULL_NONE);
    return ret;
  }