text: /******************************************************************************
   * @file     main.c
   * @version  V3.00
   * @brief    Demonstrate how to implement a USB keyboard device.
   *           It supports to use GPIO to simulate key input.
   *
   * @copyright SPDX-License-Identifier: Apache-2.0
   * @copyright Copyright (C) 2021 Nuvoton Technology Corp. All rights reserved.
   ******************************************************************************/
  #include <stdio.h>
  #include "NuMicro.h"
  #include "hid_kb.h"
  
  #define CRYSTAL_LESS        1
  #define TRIM_INIT           (SYS_BASE+0x10C)
  
  /*--------------------------------------------------------------------------*/
  uint8_t volatile g_u8EP2Ready = 0;
  
  /*--------------------------------------------------------------------------*/
  void SYS_Init(void);
  void UART0_Init(void);
  void HID_UpdateKbData(void);
  void PowerDown(void);
  int IsDebugFifoEmpty(void);
  
  void SYS_Init(void)
  {
      /*---------------------------------------------------------------------------------------------------------*/
      /* Init System Clock                                                                                       */
      /*---------------------------------------------------------------------------------------------------------*/
  
      /* Enable HIRC clock */
      CLK_EnableXtalRC(CLK_PWRCTL_HIRCEN_Msk);
  
      /* Wait for HIRC clock ready */
      CLK_WaitClockReady(CLK_STATUS_HIRCSTB_Msk);
  
      /* Select HCLK clock source as HIRC and HCLK clock divider as 1 */
      CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_HIRC, CLK_CLKDIV0_HCLK(1));
  
      /* Set PCLK0 and PCLK1 to HCLK/2 */
      CLK->PCLKDIV = (CLK_PCLKDIV_APB0DIV_DIV2 | CLK_PCLKDIV_APB1DIV_DIV2);
  
      /* Enable all GPIO clock */
      CLK->AHBCLK0 |= CLK_AHBCLK0_GPACKEN_Msk | CLK_AHBCLK0_GPBCKEN_Msk | CLK_AHBCLK0_GPCCKEN_Msk | CLK_AHBCLK0_GPDCKEN_Msk |
                      CLK_AHBCLK0_GPECKEN_Msk | CLK_AHBCLK0_GPFCKEN_Msk | CLK_AHBCLK0_GPGCKEN_Msk | CLK_AHBCLK0_GPHCKEN_Msk;
      CLK->AHBCLK1 |= CLK_AHBCLK1_GPICKEN_Msk | CLK_AHBCLK1_GPJCKEN_Msk;
  
  #if (!CRYSTAL_LESS)
      /* Enable HXT clock */
      CLK_EnableXtalRC(CLK_PWRCTL_HXTEN_Msk);
  
      /* Wait for HXT clock ready */
      CLK_WaitClockReady(CLK_STATUS_HXTSTB_Msk);
  
      /* Set core clock to 192MHz */
      CLK_SetCoreClock(FREQ_192MHZ);
  
      /* Select USB clock source as PLL/2 and USB clock divider as 2 */
      CLK_SetModuleClock(USBD_MODULE, CLK_CLKSEL0_USBSEL_PLL_DIV2, CLK_CLKDIV0_USB(2));
  #else
      /* Enable HIRC48M clock */
      CLK_EnableXtalRC(CLK_PWRCTL_HIRC48MEN_Msk);
  
      /* Waiting for HIRC48M clock ready */
      CLK_WaitClockReady(CLK_STATUS_HIRC48MSTB_Msk);
  
      /* Set core clock to 192MHz */
      CLK_SetCoreClock(FREQ_192MHZ);
  
      /* Select USB clock source as HIRC48M and USB clock divider as 1 */
      CLK_SetModuleClock(USBD_MODULE, CLK_CLKSEL0_USBSEL_HIRC48M, CLK_CLKDIV0_USB(1));
  #endif
  
      /* Enable UART0 module clock */
      CLK_EnableModuleClock(UART0_MODULE);
  
      /* Select UART0 module clock source as HIRC and UART0 module clock divider as 1 */
      CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART0SEL_HIRC, CLK_CLKDIV0_UART0(1));
  
      /* Select USBD */
      SYS->USBPHY = (SYS->USBPHY & ~SYS_USBPHY_USBROLE_Msk) | SYS_USBPHY_USBEN_Msk | SYS_USBPHY_SBO_Msk;
  
      /* Enable USBD module clock */
      CLK_EnableModuleClock(USBD_MODULE);
  
      /*---------------------------------------------------------------------------------------------------------*/
      /* Init I/O Multi-function                                                                                 */
      /*---------------------------------------------------------------------------------------------------------*/
  
      /* Set multi-function pins for UART0 RXD and TXD */
      SET_UART0_RXD_PB12();
      SET_UART0_TXD_PB13();
  
      /* USBD multi-function pins for VBUS, D+, D-, and ID pins */
      SET_USB_VBUS_PA12();
      SET_USB_D_N_PA13();
      SET_USB_D_P_PA14();
      SET_USB_OTG_ID_PA15();
  }
  
  void UART0_Init(void)
  {
      /*---------------------------------------------------------------------------------------------------------*/
      /* Init UART                                                                                               */
      /*---------------------------------------------------------------------------------------------------------*/
      /* Reset UART */
      SYS_ResetModule(UART0_RST);
  
      /* Configure UART and set UART Baudrate */
      UART_Open(UART0, 115200);
  }
  
  void HID_UpdateKbData(void)
  {
      int32_t i;
      uint8_t *pu8Buf;
      uint32_t u32Key = 0xF;
      static uint32_t u32PreKey;
  
      if(g_u8EP2Ready)
      {
          pu8Buf = (uint8_t *)(USBD_BUF_BASE + USBD_GET_EP_BUF_ADDR(EP2));
  
          /* If PH.0 = 0, just report it is key 'a' */
          u32Key = (PH->PIN & (1 << 0)) ? 0 : 1;
  
          if(u32Key == 0)
          {
              for(i = 0; i < 8; i++)
              {
                  pu8Buf[i] = 0;
              }
  
              if(u32Key != u32PreKey)
              {
                  /* Trigger to note key release */
                  USBD_SET_PAYLOAD_LEN(EP2, 8);
              }
          }
          else
          {
              u32PreKey = u32Key;
              pu8Buf[2] = 0x04; /* Key a */
              USBD_SET_PAYLOAD_LEN(EP2, 8);
          }
      }
  }
  
  void PowerDown(void)
  {
      uint32_t u32TimeOutCnt;
  
      /* Unlock protected registers */
      SYS_UnlockReg();
  
      printf("Enter power down ...\n");
      u32TimeOutCnt = SystemCoreClock; /* 1 second time-out */
      while(!IsDebugFifoEmpty())
          if(--u32TimeOutCnt == 0) break;
  
      /* Wakeup Enable */
      USBD_ENABLE_INT(USBD_INTEN_WKEN_Msk);
  
      CLK_PowerDown();
  
      /* Clear PWR_DOWN_EN if it is not clear by itself */
      if(CLK->PWRCTL & CLK_PWRCTL_PDEN_Msk)
          CLK->PWRCTL ^= CLK_PWRCTL_PDEN_Msk;
  
      printf("device wakeup!\n");
  
      /* Lock protected registers */
      SYS_LockReg();
  }
  
  /*---------------------------------------------------------------------------------------------------------*/
  /*  Main Function                                                                                          */
  /*---------------------------------------------------------------------------------------------------------*/
  int32_t main(void)
  {
  #if CRYSTAL_LESS
      uint32_t u32TrimInit;
  #endif
  
      /* Unlock protected registers */
      SYS_UnlockReg();
  
      /* Init System, peripheral clock and multi-function I/O */
      SYS_Init();
  
      /* Init UART for printf */
      UART0_Init();
  
      printf("\n");
      printf("+--------------------------------------------------------+\n");
      printf("|          NuMicro USB HID Keyboard Sample Code          |\n");
      printf("+--------------------------------------------------------+\n");
      printf("If PH.0 = 0 or press BTN0 button, just report it is key 'a'.\n");
  
      USBD_Open(&gsInfo, HID_ClassRequest, NULL);
  
      /* Endpoint configuration */
      HID_Init();
      USBD_Start();
  
      NVIC_EnableIRQ(USBD_IRQn);
  
  #if CRYSTAL_LESS
      /* Backup default trim */
      u32TrimInit = M32(TRIM_INIT);
  #endif
  
      /* Clear SOF */
      USBD->INTSTS = USBD_INTSTS_SOFIF_Msk;
  
      /* start to IN data */
      g_u8EP2Ready = 1;
  
      while(1)
      {
  #if CRYSTAL_LESS
          /* Start USB trim if it is not enabled. */
          if((SYS->HIRCTCTL & SYS_HIRCTCTL_FREQSEL_Msk) != 1)
          {
              /* Start USB trim only when SOF */
              if(USBD->INTSTS & USBD_INTSTS_SOFIF_Msk)
              {
                  /* Clear SOF */
                  USBD->INTSTS = USBD_INTSTS_SOFIF_Msk;
  
                  /* Re-enable crystal-less */
                  SYS->HIRCTCTL = 0x01;
                  SYS->HIRCTCTL |= SYS_HIRCTCTL_REFCKSEL_Msk | SYS_HIRCTCTL_BOUNDEN_Msk | (8 << SYS_HIRCTCTL_BOUNDARY_Pos);
              }
          }
  
          /* Disable USB Trim when error */
          if(SYS->HIRCTISTS & (SYS_HIRCTISTS_CLKERRIF_Msk | SYS_HIRCTISTS_TFAILIF_Msk))
          {
              /* Init TRIM */
              M32(TRIM_INIT) = u32TrimInit;
  
              /* Disable crystal-less */
              SYS->HIRCTCTL = 0;
  
              /* Clear error flags */
              SYS->HIRCTISTS = SYS_HIRCTISTS_CLKERRIF_Msk | SYS_HIRCTISTS_TFAILIF_Msk;
  
              /* Clear SOF */
              USBD->INTSTS = USBD_INTSTS_SOFIF_Msk;
          }
  #endif
  
          /* Enter power down when USB suspend */
          if(g_u8Suspend)
              PowerDown();
  
          HID_UpdateKbData();
      }
  }
  