利用stm32f103zetl单片机同时生成一个频率为 4-5KHz占空比为50%，峰峰值为 3.3v的方波，频率可以通过按键直接调整及步进可调，步进小于等于1Hz。和频率为12-15KHz峰峰值为2.2v的正弦波，频率可以通过按键直接调整及步进可调，步进小于等于16Hz。生成keil5代码

以下是基于Keil5的代码，实现了同时生成一个频率为 4-5KHz占空比为50%，峰峰值为 3.3v的方波和频率为12-15KHz峰峰值为2.2v的正弦波，并且可以通过按键直接调整及步进可调，步进小于等于1Hz和16Hz。

#include "stm32f10x.h"

// 定义时钟频率和周期
#define SYS_CLK_FREQ    72000000
#define CYCLE_FREQ      5000
#define SINE_FREQ_MIN   12000
#define SINE_FREQ_MAX   15000
#define SINE_AMP        2048
#define SINE_OFFSET     2048

// 定义按键引脚
#define KEY_PORT        GPIOA
#define KEY_UP_PIN      GPIO_Pin_0
#define KEY_DOWN_PIN    GPIO_Pin_1

// 定义输出引脚
#define SQUARE_OUT_PORT GPIOB
#define SQUARE_OUT_PIN  GPIO_Pin_0

#define SINE_OUT_PORT   GPIOB
#define SINE_OUT_PIN    GPIO_Pin_1

// 定义计数器和频率变量
volatile uint32_t square_counter = 0;
volatile uint32_t sine_counter = 0;
volatile uint32_t square_freq = CYCLE_FREQ;
volatile uint32_t sine_freq = SINE_FREQ_MIN;

// 初始化函数声明
void RCC_Configuration(void);
void GPIO_Configuration(void);
void TIM_Configuration(void);
void EXTI_Configuration(void);
void NVIC_Configuration(void);

// 主函数
int main(void)
{
    // 初始化时钟、GPIO、定时器和中断控制器
    RCC_Configuration();
    GPIO_Configuration();
    TIM_Configuration();
    NVIC_Configuration();

    // 循环等待
    while (1);
}

// RCC配置函数
void RCC_Configuration(void)
{
    // 打开GPIO和定时器1的时钟
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO | RCC_APB2Periph_TIM1, ENABLE);
}

// GPIO配置函数
void GPIO_Configuration(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    // 配置按键引脚为输入模式
    GPIO_InitStructure.GPIO_Pin = KEY_UP_PIN | KEY_DOWN_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_Init(KEY_PORT, &GPIO_InitStructure);

    // 配置方波输出引脚为复用模式
    GPIO_InitStructure.GPIO_Pin = SQUARE_OUT_PIN;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_Init(SQUARE_OUT_PORT, &GPIO_InitStructure);

    // 配置正弦波输出引脚为复用模式
    GPIO_InitStructure.GPIO_Pin = SINE_OUT_PIN;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_Init(SINE_OUT_PORT, &GPIO_InitStructure);
}

// 定时器配置函数
void TIM_Configuration(void)
{
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    TIM_OCInitTypeDef TIM_OCInitStructure;

    // 初始化定时器1
    TIM_TimeBaseStructure.TIM_Period = SYS_CLK_FREQ / square_freq - 1;
    TIM_TimeBaseStructure.TIM_Prescaler = 0;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);

    // 配置定时器1通道1为PWM模式
    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = (SYS_CLK_FREQ / square_freq) / 2 - 1;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC1Init(TIM1, &TIM_OCInitStructure);

    // 配置定时器1为触发源
    TIM_SelectOutputTrigger(TIM1, TIM_TRGOSource_Update);

    // 初始化定时器3
    TIM_TimeBaseStructure.TIM_Period = SYS_CLK_FREQ / SINE_FREQ_MIN - 1;
    TIM_TimeBaseStructure.TIM_Prescaler = 0;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

    // 配置定时器3通道2为PWM模式
    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = SINE_AMP + SINE_OFFSET - 1;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC2Init(TIM3, &TIM_OCInitStructure);

    // 配置定时器3为触发源
    TIM_SelectOutputTrigger(TIM3, TIM_TRGOSource_Update);

    // 启动定时器1和定时器3
    TIM_Cmd(TIM1, ENABLE);
    TIM_Cmd(TIM3, ENABLE);
}

// 外部中断配置函数
void EXTI_Configuration(void)
{
    EXTI_InitTypeDef EXTI_InitStructure;

    // 配置按键引脚为外部中断线
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource0);
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource1);

    // 配置按键引脚为下降沿触发
    EXTI_InitStructure.EXTI_Line = EXTI_Line0 | EXTI_Line1;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);
}

// 中断控制器配置函数
void NVIC_Configuration(void)
{
    NVIC_InitTypeDef NVIC_InitStructure;

    // 配置定时器1更新中断
    NVIC_InitStructure.NVIC_IRQChannel = TIM1_UP_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    // 配置定时器3更新中断
    NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    // 配置按键中断
    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn | EXTI1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

// 定时器1更新中断服务函数
void TIM1_UP_IRQHandler(void)
{
    // 清除定时器1更新中断标志
    TIM_ClearITPendingBit(TIM1, TIM_IT_Update);

    // 计数器加1
    square_counter++;

    // 如果计数器达到一个周期，则重新设定占空比，计数器清零
    if (square_counter >= (SYS_CLK_FREQ / square_freq))
    {
        TIM_SetCompare1(TIM1, (SYS_CLK_FREQ / square_freq) / 2 - 1);
        square_counter = 0;
    }
}

// 定时器3更新中断服务函数
void TIM3_IRQHandler(void)
{
    // 清除定时器3更新中断标志
    TIM_ClearITPendingBit(TIM3, TIM_IT_Update);

    // 计数器加1
    sine_counter++;

    // 如果计数器达到一个周期，则重新设定占空比，计数器清零
    if (sine_counter >= (SYS_CLK_FREQ / sine_freq))
    {
        TIM_SetCompare2(TIM3, SINE_AMP * sinf(2 * 3.1415926f * sine_counter / (SYS_CLK_FREQ / sine_freq)) + SINE_OFFSET - 1);
        sine_counter = 0;
    }
}

// 按键中断服务函数
void EXTI0_IRQHandler(void)
{
    // 清除按键0中断标志
    EXTI_ClearITPendingBit(EXTI_Line0);

    // 频率减小
    if (square_freq > CYCLE_FREQ)
    {
        square_freq -= 1;
        TIM_SetAutoreload(TIM1, SYS_CLK_FREQ / square_freq - 1);
    }
}

void EXTI1_IRQHandler(void)
{
    // 清除按键1中断标志
    EXTI_ClearITPendingBit(EXTI_Line1);

    // 频率增加
    if (square_freq < (CYCLE_FREQ + 1))
    {
        square_freq += 1;
        TIM_SetAutoreload(TIM1, SYS_CLK_FREQ / square_freq - 1);
    }
    else if (sine_freq < SINE_FREQ_MAX)
    {
        sine_freq += 16;
        TIM_SetAutoreload(TIM3, SYS_CLK_FREQ / sine_freq - 1);
    }
    else
    {
        sine_freq = SINE_FREQ_MIN;
        TIM_SetAutoreload(TIM3, SYS_CLK_FREQ / sine_freq - 1);
    }
}