<div class="document"> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">1、项目功能介绍</h3> <hr class="horizontal-splitline normal-bold-2"> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"><span style="color:#000000;font-size:14px;">基于R7FA2E1A72DFL芯片的桌面电子时钟设计，通过四位0.56寸共阴极数码管进行时间、温度等显示，采用DHT11温湿度传感器采集环境温湿度，同时还有锂电池充电模块、蜂鸣器、触摸控制电路、、SWD下载以及串口下载等模块。</span></p> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"> </p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2、硬件部分</h3> <hr class="horizontal-splitline normal-bold-2"> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"><span style="color:#95a5a6;font-size:14px;"><img src="//image.lceda.cn/pullimage/WlsBNEg3IjdzFP6ldhjZ2ACt2BZlhhZAtptRPKE3.png" alt="" width="1200" height="852"></span></p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.1电源输入电路</h3> <p>电源电路主要由TYPE-C接口以及电源指示灯组成，R1作为电源指示灯的限流电阻，LED1作为电源指示灯，闭合开关会点亮进行提示。</p> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"><span style="color:#95a5a6;font-size:14px;"><img src="//image.lceda.cn/pullimage/ylC42lDzfQmzVZxgGRv5lgEA1lI4RUIp8ggLfdfX.png" alt="" width="592" height="327"></span></p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.2主控电路</h3> <p><img src="//image.lceda.cn/pullimage/9r4ii5ezDG1EMmrgifHZpABcW1Q9AQTBppw0smEc.png" alt="" width="1165" height="478"></p> <p>主控单片机使用的是R7FA2E1A72DFL，在电源输入部分加入100nf电容进行电源滤波，VCL引脚用于稳定内部电源的平滑电容，需要将该引脚连接应该4.7uf的电容到VSS引脚。</p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.3复位按键</h3> <p><img src="//image.lceda.cn/pullimage/JFen3AaB3OSaRRBfBmSV6UN9V0CpOyZj85kwIaaS.png" alt="" width="383" height="304"></p> <p> 按键RST按键，主控的RST引脚被拉低，系统进入复位状态，松开RST按键，主控的RST引脚恢复高电平，系统重新进行工作状态，完成复位。</p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.4boot按键</h3> <p><img src="//image.lceda.cn/pullimage/J2HjlE6BPYWqAni4XcxKCp0O5tft6Qm5V3C5Rkzp.png" alt="" width="491" height="307"></p> <p>当BOOT1按键没有按下时，BOOT引脚为高电平，单片机进入Single-chip模式，也就是正常工作模式，当按下按键时，BOOT引脚低电平，单片机进入SCI-BOOT模式，也就是程序下载模式，可以通过这个按键控制单片机进行程序下载或者正常运行。</p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.5触摸控制电路</h3> <p><img src="//image.lceda.cn/pullimage/5EYqUEknzBZqUPWmRGBHxJIwBptsKXeyXu8FMGUt.png" alt="" width="582" height="468"></p> <p>由于R7FA2E1A72DFL主控芯片自带触摸功能，在触摸线上加入560欧的阻尼电容以及适当的电容来稳定触摸信号，已足够灵敏和准确。</p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.6触摸控制电路</h3> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"><img src="//image.lceda.cn/pullimage/87jeY4hYTPWGFTkjwy9WswA97sUkVhV6P577yKvt.png" alt="" width="581" height="466"></h3> <p> 采用四个按键作为时钟控制或者其余功能使用。</p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.7DHT11温湿度传感器</h3> <p><img src="//image.lceda.cn/pullimage/WIBWZsLf07fRPP3U9WLKsWPqCe3m4SfKB9xQChHJ.png" alt="" width="544" height="471"></p> <p>采用DHT11温湿度传感器检测环境温湿度，DHT11是单总线通信方式，需要在总线外接一个上拉电阻，当总线闲置时，其状态为高电平。</p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.8蜂鸣器</h3> <p><img src="//image.lceda.cn/pullimage/nrOIO5VfXybJrml7HqL7YhdWWQA8OL56pzzxty2a.png" alt="" width="271" height="340"></p> <p> 通过NPN三极管控制无源蜂鸣器的负极，R5为限流电阻，R6的作用是在芯片刚上电或断电的时候提供一个可靠的电位，防止干扰，这里的电磁无源蜂鸣器是感性负载，加入D2二极管作为续流二极管防止烧坏。</p> <p> </p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.9共阴极数码管</h3> <p><img src="//image.lceda.cn/pullimage/CVhCKhNeiLZa8xYqaXqh4H7TTvSEl6kqgavpvKQD.png" alt="" width="487" height="480"></p> <p>采用0.56寸共阴极数码管用于显示时间、温湿度等信息。</p> <p> </p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.10锂电池充放电部分</h3> <p><img src="//image.lceda.cn/pullimage/Uc90oCQh73W95PKjfddzE4y6svxDPifAWMod2izF.png" alt="" width="905" height="324"></p> <p>通过一个TP5056锂电池充电芯片给电池进行充电，当TYPE-C接口接入时，同时会给锂电池充电，确保电量充足。LED2、LED3作为充电状态指示灯，R12是充电电流反馈电阻，通过改变R12的阻值，可以改变整体的充电电流。</p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.11串口下载</h3> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"><img src="//image.lceda.cn/pullimage/0lvKdDjUpxWWSRhzc0yt6X7hVkpYAiPe7mO4WNKK.png" alt="" width="248" height="322"></h3> <p>通过2.54*4P接口将串口引脚进行引出，用于串口下载与调试。</p> <p> </p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.12SWD下载</h3> <p><img src="//image.lceda.cn/pullimage/UsjOxiT7z6QkcGoyXPY88bP8bguNq2w6myRPdNlc.png" alt="" width="282" height="325"></p> <p>通过2.54*4P接口将SWD引脚进行引出，用于SWD模式下载与调试。</p> <p> </p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.13M3铜柱接口</h3> <p> <img src="//image.lceda.cn/pullimage/scICbPqSHsu32wcyuV6QtWX9BUmHLSrO2vkffLiO.png" alt="" width="968" height="427"></p> <p>通过四个M3的螺丝孔用于固定板子。</p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">2.14PCB走线</h3> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"><img src="//image.lceda.cn/pullimage/1gSwDunG59ecU14X4eZzsvfWzAHltWeCigVfrs09.png" alt=""></p> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt pap-left-indent-1.6em" style="line-height:1.8;"> </p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">3、BOM清单</h3> <hr class="horizontal-splitline normal-bold-2"> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"><img src="//image.lceda.cn/pullimage/hYx1ZuMsHGwGsI0SakfMYg7gGjCxkA63SelEFIX2.png" alt="" width="1200" height="602"></p> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"> </p> <h3 class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;">4、大赛LOGO验证</h3> <hr class="horizontal-splitline normal-bold-2"> <p style="line-height:1.8;"><img src="//image.lceda.cn/pullimage/XrVmfZwjFBPbB2x7rGMRP4zbrcodCCQoVuvGVKKo.png" alt="" width="1000" height="190"></p> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"> </p> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"> </p> <p class="paragraph text-align-type-left pap-line-1.3 pap-line-rule-auto pap-spacing-before-3pt pap-spacing-after-3pt" style="line-height:1.8;"> </p> </div>