/*!

   \file    main.c

   \brief   USART printf

   \version 2025-01-16, V1.4.0, firmware for GD32VW55x

*/

/*

   Copyright (c) 2025, GigaDevice Semiconductor Inc.

   Redistribution and use in source and binary forms, with or without modification,

are permitted provided that the following conditions are met:

   1. Redistributions of source code must retain the above copyright notice, this

      list of conditions and the following disclaimer.

   2. Redistributions in binary form must reproduce the above copyright notice,

      this list of conditions and the following disclaimer in the documentation

      and/or other materials provided with the distribution.

   3. Neither the name of the copyright holder nor the names of its contributors

      may be used to endorse or promote products derived from this software without

      specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.

IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,

INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,

WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY

OF SUCH DAMAGE.

*/

#include "gd32vw55x.h"

#include "systick.h"

#include <stdio.h>

void com_usart_init(void);

/*!

   \brief      main function

   \param[in]  none

   \param[out] none

   \retval     none

*/

int main(void)

{

   /* initialize the COM */

systick_config();

   com_usart_init();

   gpio_mode_set(GPIOA, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO_PIN_11);

   gpio_bit_reset(GPIOA,GPIO_PIN_11);

   //上面两行是我在PA11和3.3V间接了个LED来观察程序是否执行

   while(1){

   }

}

//下面代码改自官方串口例程，用的是UART1

/*!

   \brief      initialize the USART configuration of the COM

   \param[in]  none

   \param[out] none

   \retval     none

*/

void com_usart_init(void)

{

   /* enable COM GPIO clock */

   rcu_periph_clock_enable(RCU_GPIOA);//GPIOA时钟使能

   /* enable USART clock */

   rcu_periph_clock_enable(RCU_UART1);//UART1时钟使能

   //GPIO复用模式配置

   /* connect port to USART TX */

   gpio_af_set(GPIOA, GPIO_AF_0, GPIO_PIN_4);

   /* connect port to USART RX */

   gpio_af_set(GPIOA, GPIO_AF_0, GPIO_PIN_5);

   //配置GPIO模式和速率

   /* configure USART Tx as alternate function push-pull */

   gpio_mode_set(GPIOA, GPIO_MODE_AF, GPIO_PUPD_PULLUP, GPIO_PIN_4);

   gpio_output_options_set(GPIOA, GPIO_OTYPE_PP, GPIO_OSPEED_25MHZ, GPIO_PIN_4);

   /* configure USART Rx as alternate function push-pull */

   gpio_mode_set(GPIOA, GPIO_MODE_AF, GPIO_PUPD_PULLUP, GPIO_PIN_5);

   gpio_output_options_set(GPIOA, GPIO_OTYPE_PP, GPIO_OSPEED_25MHZ, GPIO_PIN_5);

   /* USART configuration */

   usart_deinit(UART1);

   usart_word_length_set(UART1, USART_WL_8BIT);

   usart_stop_bit_set(UART1, USART_STB_1BIT);

   usart_parity_config(UART1, USART_PM_NONE);

   usart_baudrate_set(UART1, 115200U);

   usart_receive_config(UART1, USART_RECEIVE_ENABLE);

   usart_transmit_config(UART1, USART_TRANSMIT_ENABLE);

   usart_enable(UART1);

   // 使能USART中断

   eclic_irq_enable(UART1_IRQn, 0, 0);

   // 使能串口接收中断

   usart_interrupt_enable(UART1, USART_INT_RBNE);

}