记录STM32 USB OTG ID 管脚初始化以及变化过程

发布于 2019-11-16 14:47:08 浏览：3377 订阅该版

使用的是STM32F411E-DISCO板子， CubeMX并没有支持OTG双向的代码生成，只能找以前标准库的代码看（**STSW-STM32046**）
标准库关于ID脚的初始化：
```c
 /* Configure ID pin */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_OTG1_FS);
```

照着写：
```c
    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**USB_OTG_FS GPIO Configuration    
    PA11     ------> USB_OTG_FS_DM
    PA12     ------> USB_OTG_FS_DP 
    */
    GPIO_InitStruct.Pin = GPIO_PIN_11 | GPIO_PIN_12;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF10_OTG_FS;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

GPIO_InitStruct_ID.Pin = GPIO_PIN_10;
    GPIO_InitStruct_ID.Mode = GPIO_MODE_AF_OD;
    GPIO_InitStruct_ID.Pull = GPIO_PULLUP;
    GPIO_InitStruct_ID.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct_ID.Alternate = GPIO_AF10_OTG_FS;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct_ID);

/* Peripheral clock enable */
    __HAL_RCC_USB_OTG_FS_CLK_ENABLE();
    /* USB_OTG_FS interrupt Init */
    HAL_NVIC_SetPriority(OTG_FS_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(OTG_FS_IRQn);
```

USB开中断
```c
    cfg.phy_itface = USB_OTG_EMBEDDED_PHY;
    USB_CoreInit(stm32_otg, cfg);
    stm32_otg->GINTMSK |= USB_OTG_GINTMSK_OTGINT;
    stm32_otg->GINTMSK |= USB_OTG_GINTMSK_CIDSCHGM;
    USB_EnableGlobalInt(stm32_otg);
```
OTG_FS_IRQHandler中断处理
```c
void OTG_FS_IRQHandler(void)
{
    rt_uint32_t global_interrupt;
    rt_err_t ret = RT_EOK;

rt_interrupt_enter();

global_interrupt = USB_ReadInterrupts(stm32_otg);

USB_ClearInterrupts(stm32_otg, ~global_interrupt);

if ((global_interrupt & common_interrupt) != 0)
    {
        ret = common_interrupt_proc(stm32_otg, global_interrupt);
    }

if (ret != RT_EOK)
        return;

if (stm32_otg->GOTGCTL & USB_OTG_GOTGCTL_CIDSTS)
 {
 rt_kprintf("CIDSTS: B ");

if (stm32_otg->GOTGCTL & USB_OTG_GOTGCTL_BSVLD)
 {
 rt_kprintf("BSVLD valid ");
 }
 else
 {
 rt_kprintf("BSVLD not valid ");
 }
 }
 else
 {
 rt_kprintf("CIDSTS: A ");

if (stm32_otg->GOTGCTL & USB_OTG_GOTGCTL_ASVLD)
 {
 rt_kprintf("ASVLD valid ");
 }
 else
 {
 rt_kprintf("ASVLD not valid ");
 }
 }

if (USB_GetMode(stm32_otg) == USB_DEVICE_MODE)
    {

if ((global_interrupt & device_interrupt) != 0)
            device_interrupt_proc(stm32_otg, global_interrupt);
    }
    else
    {

if ((global_interrupt & host_interrupt) != 0)
            host_interrupt_proc(stm32_otg, global_interrupt);
    }

rt_interrupt_leave();
}
```
运行结果：
刚开始OTG的角色为B-device，插入OTG线切换为A-device，拔出切换回B-device

![init.png](https://oss-club.rt-thread.org/uploads/201911/16/143726bnqb8ltfj34nyysq.png)
![plugin.png](https://oss-club.rt-thread.org/uploads/201911/16/143727lfdlwzpvzbvcdhjl.png)
![plugout.png](https://oss-club.rt-thread.org/uploads/201911/16/143727sedjhhdy1lipjneb.png)