<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">1、项目功能介绍</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;">     热敏微型打印机是一种嵌入式系统常用的硬拷贝输出装置，与大家的生活密切相关，例如刷信用卡有信用卡回执单，点外卖有点单小票，用纸制的打印票据作为双方交易的凭据，是互联网无纸化应用的重要补充。热敏微型打印机具有输出分辨率高，打印速度快，数据处理和实时控制都有较高的要求，如果采用传统的8位单片机来完成设计，会带来系统的复杂性和硬件成本高的弊端，而采用新一代国产ARM核M0芯片进行相应的设计，就能达到性能与价格的完美平衡，保证性能的前提下，达到了成本最低。</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;">      采用国民技术<span style="color: #e03e2d;">N32G031C8L7</span>芯片为主控的热敏微型打印机控制板作品成品图如下，该控制板配套的热敏打印头为常见的FTP628MCL-101或其它兼容国产热敏打印机头如精芯科技公司的<span style="color: #e03e2d;">JX-2R-01</span>机头，打印机使用的字库为由深圳高通半导体有限公司推出的<span style="color: #e03e2d;">GT30L32S4W</span>打印机专用字库芯片。</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;">    本次设计的打印机控制板为了方便调试和使用，增加了USB转串口功能，使用了沁恒公司的<span style="color: #e03e2d;">CH340C</span>完成通讯，供电部分使用了TI公司的DCDC芯片<span style="color: #e03e2d;">TPS54331</span>完成12V变换成5V供打印系统使用的设计。</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;">                                                         <img src="//image.lceda.cn/pullimage/o3eHzz2yk80xGCPZXOQIu63rNv0IVzMFXcXwXECp.jpeg" alt="国民技术N32G031C8L7热敏微型打印机方案板" width="1276" height="1702"></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、项目属性</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;">       本项目采用国民技术32位单片机N32G031C8L7为主控，利用其丰富的资源实现热敏打印机控制的全部功能。全套软硬件系作者原创，N32G031C8L7芯片拥有64K Flash程序和8K SRAM空间，自带高精度RC振荡器，12位ADC，3个UART和2路SPI硬件，使得本机硬件电路简洁，性价比极高，系同类产品中降本增效的典范。</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;">       下图为采用传统8位单片机实现的5V串口热敏微打控制板和采用32位ARM芯片N32G031C8L7为主控的热敏微打控制板对照图。<img src="//image.lceda.cn/pullimage/F1T0BwyTi1s8c1UAp6DgTTSFTj4AthTbAgPPa938.jpeg" alt="" width="1702" height="1276"></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、开源协议</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;">本项目采用GPL3.0开源协议</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、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;">   <strong> 4.1、硬件部分功能组成如下：</strong></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;"><img src="//image.lceda.cn/pullimage/bhFvEC6Y5bHhHhSwkKi5rFHT5mtRMFZhTfJjvVNZ.png" alt="" width="724" height="483"></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;"><strong> 4.2、硬件电路构成框图如下图所示：</strong></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;"><img src="//image.lceda.cn/pullimage/gZokd3BvzfJfL1E3kFRoyGmNRtfy0cdIHgRw28RW.png" alt="" width="602" height="544"></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;"><strong>4.3、控制板电路原理总图</strong>如下所示，完整清晰的原理图请下载附件中的PDF格式文件查看。</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;"><img src="//image.lceda.cn/pullimage/KGP2HSclZTsHKwcddCgIebffg7tZEwqRnvBvAxg5.png" alt="" width="820" height="535"></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;"><strong>4.4.1、电路功能解说-单片机最小系统单元：</strong></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;"><img src="//image.lceda.cn/pullimage/NEjYUqWI9GBgNYNww6Ft3aigvEw24dYSGkBYeIxd.png" alt="" width="617" height="424"></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;">      电路参考官方评估板进行设计，注意芯片的VDD引脚上都要就近放置104电容，保证芯片的工作稳定性，并在48脚附近额外增加了1只10uF的陶瓷电容滤波。44脚Boot0采用上拉到VDD及跳线到地的设计，如果要使用芯片的ISP功能更新固件，跳线断开，Boot0上拉，运行国民技术官方设计的上位机专用下载软件即可。如果要用Jlink仿真调试固件，需要Boot0短路到地。</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;">     芯片的SPI1模块与字库相连，使用芯片的高速硬件SPI单元读取字库中的字符点阵。</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;">     连接到PB2上的TM信号为打印机温度热敏电阻输出电压检测引脚，使用芯片的ADC单元读取打印头实时温度值，超出限定值时，暂停加热操作，待温度恢复正常后继续进行后续打印内容。</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;">      连接到PB0引脚上的PRN_PHE信号为缺纸检测信号，打印头有纸时，光电开关光敏管有输出，此引脚为高电平，缺纸时，光敏管无法接收到反射光，无输出电流，此引脚为低电平。</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;"><strong>4.4.2、电路功能解说-电源部分：</strong></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;"><strong><img src="//image.lceda.cn/pullimage/XsMzGa7kkSt4awkXDS3jNiXjoIXuOd97MBLhPiBV.png" alt="" width="772" height="264"></strong></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="font-size: 12px;">    </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;"><strong>    </strong>电路按最大输出5V-3A设计，输出续流二极管用的是3A的肖特基快恢复型二极管B340K，由于此芯片采用高达570KHz的固定开关频率，因而可以使用较小的变换电感6.8uH和较小的输出电容即可。</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;">   芯片各引脚功能描述如下图：</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;"><img src="//image.lceda.cn/pullimage/TyMNFj1aIBqolkVYCc7GbnZhGr58Ncit9cZrP7Ni.png" alt="" width="1079" height="441">   设计时需注意3号引脚功能：此引脚为允许工作引脚，当低于1.25V时，芯片停止工作，如果悬空，为一至保持工作状态，推荐设计时用2个电阻分压实现低电压锁定工作的。按图中设计值代入计算得出输入低于10.06V时会停止输出。计算公式为（1143/143)*1.25V = 10.0616197V</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;"><strong>    </strong></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;"><strong>4.4.3、电路功能解说-电机驱动部分：</strong></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;"><strong><img src="//image.lceda.cn/pullimage/2e6gYMdK9CVkpvOuDfuYk7S4pGs5UFQoPja59i7e.png" alt="" width="382" height="206"></strong></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;">电机驱动采用杭州中科微电子生产的AT8548电机芯片，具有Pin To Pin替代进口，价格低廉的优势。该芯片性能如下图所示。<img src="//image.lceda.cn/pullimage/N6EpcG4eOgcHu3DySSIb6hnScUxpHVXebGNESxm1.png" alt="" width="761" height="405"></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;"><strong>4.4.4、电路功能解说-字库接口部分：</strong></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;"><strong><img src="//image.lceda.cn/pullimage/mKLLbBWVe0TKNVZ0XFJ8bIMaVh5BcTUFBJ03ObPv.png" alt="" width="427" height="193"></strong></p>     字库采用深圳高通半导体有限公司的打印机专用横置横排点阵字体，具体规格如下图：</div> <div class="document"><img src="//image.lceda.cn/pullimage/n9jLsMgfcVVydTmcVyQw533w91fWZbe2wbSIoQiI.png" alt="" width="668" height="250"></div> <div class="document"> <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;"><strong>4.4.5、电路功能解说-USB转串口部分：</strong></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;"><strong><img src="//image.lceda.cn/pullimage/g2Py7JtIFh5EHB8oc8crPgdLoU1RRf1HS5OfhTGz.png" alt="" width="701" height="325"></strong></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;">     USB转串口部分采用南京沁恒公司的CH340C，该芯片内置振荡器满足USB通讯要求，简化了电路和生产。</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;"><strong>4.4.6、电路功能解说-打印头接口部分：</strong></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;"><strong><img src="//image.lceda.cn/pullimage/fvJl6oBUubFdtQDXyz4QuTKfUakqfYbsp107xrQg.png" alt="" width="432" height="509"></strong></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;"><strong>   </strong>  热敏打印头内部结构其实很简单，相当于内置384个串行灯炮加热用，数据串行传输与常用的HC595扩充输出架构是一样一样的。上图中R5为检测纸的光电开关发光二极管限流电阻，R6是光电开关输出光电三极管负载电阻，R9为打印头测温热敏电阻分压上置电阻，与热敏电阻分压后送单片机AD口测量。</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;">内部结构如下图所示：</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;"><img src="//image.lceda.cn/pullimage/AmuwRddbNyNEh2idryz6GaE18eVM3d17KQGyfXXN.png" alt="" width="746" height="559">注意事项，STB信号为高时，输出寄存器的内容 触发加热单元加热，单片机上电初始化后应将此引脚拉低，以免长期加热损伤打印头。</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;">5、软件部分</h3> <p>     软件采用MDK5.27版本编译，实现了中文32X32字符串打印，英文32X16字符串打印，固定图形打印等功能，软件工程内容如下图：</p> <p><img src="//image.lceda.cn/pullimage/H6s9GGS2Y85ryYsLXNm5AO2m0mzC2HZdLNFiZ9Z1.png" alt="" width="1280" height="761"></p> <p>       全部工程源代码打包后在附件中可以下载，软件采用分层驱动，底层调用官方的库文件实现单片机硬件的初始化和驱动接口。</p> <p><strong>5.2.1、软件功能解说-步进电机驱动</strong></p> <p>       电机采用2相4步驱动，电机转动2步，走纸机构带动纸卷前进1点行，相关代码如下图，注意电机每走一步需换相，走步时要记忆当前位置信息。</p> <p><img src="//image.lceda.cn/pullimage/QMqP76gD9zrSVW8WqNFkXXeMQOHzchYBfVOWbeFd.png" alt="" width="619" height="331"></p> <strong>5.2.2、软件功能解说-1点行数据输出到打印头锁存器函数</strong></div> <div class="document">        打印一点行数据是实现图形和字符打印的核心功能函数，一点行384个Bit点，内容预先存放到38字节的行点阵缓冲区中，相关实现代码如下图所示。</div> <div class="document"> <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/zMoitua02txPn0HnLDhSFL6We4j8mWgmVP2hyhIN.png" alt="" width="737" height="143"></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;"><strong>5.2.3、软件功能解说-一行汉字字符打印功能函数</strong></p> <strong>     </strong>打印一行汉字是调用前面介绍的输出一点行打印数据，然后加热，走纸一点行，如此循环32次即完成一行32点阵字符的打印功能，相关代码截图如下所示：</div> <div class="document"><img src="//image.lceda.cn/pullimage/KaNeTw2KpR2lyeyte0XJvDh3UUJUAWMONxwlaILv.png" alt="" width="986" height="579"></div> <div class="document"><strong>5.3、程序烧写说明</strong></div> <div class="document">      将板上的Boot0引脚断开跳线，使芯片上电运行ISP加载程序，此时即可以使用官方ISP工具软件通过串口直接加载固件到单片机，然后将Boot0引脚置低，重新上电运行固件测试功能，相关软件截图如下所示：</div> <div class="document"><img src="//image.lceda.cn/pullimage/iLs7VmZd6fj4ER6n642UgnD7Xrrr9hUeBSHnAyFQ.png" alt="" width="983" height="707"></div> <div class="document"> <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;">6、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;"> BOM表由电路原理图直接导出的Excel表，相关截图如下：完整的材料表详见附件文件内容</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;"><img src="//image.lceda.cn/pullimage/ZngeYBW1JijoP6J0vDPYDBeEQAJF0oaDVMp2Pdr6.png" alt="" width="1091" height="609"></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;">7、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/HYWbxKWfH0Fcr3HMAgkssXg5O6x9gOXuPzLneJO1.jpeg" alt="" width="741" height="764"></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;"> 8、演示您的项目并录制成视频上传</h3> <hr class="horizontal-splitline normal-bold-2"> <p 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>