SV6301A Firmware v0.7.0 features:
1. Support NanoVNA-App（as the original author of NanoVNA-App has not checked the PR yet, only the SYSJOINT branch version is currently available）;
    NanoVNA-App_by_SYSJOINT download:
    https://github.com/sysjoint-tek/NanoVNA-App/releases
    https://www.sysjoint.com/ueditor/php/upload/file/NanoVNA-App_by_SYSJOINT.zip
2. Support PC software "SVxx01A Tools". User can demonstrate the operation of SV6301A on PC.
    SVxx01A Tools download: https://www.sysjoint.com/ueditor/php/upload/file/SVXX01A_Tools.zip
3. Optimized the calibration kit editor:
    (a) Complete the input parameters of the calibrate kit;
    (b) Parameter inputing supports scientific notation;
    (c) User defined calibration kit name;
    (d) Calibrations kit can be saved/recalled;
4. Optimized the S21 impedance measurement;
5. Optimized the calibration file save/recall dialog;
6. Optimized the user experience for menu and keyboard;
7. New serial command 'vbat', 'capture' for NanoVNA-App;
8. Some bug fix;


SV6301A v0.7.0固件特性：
1、支持NanoVNA-App上位机（由于NanoVNA-APP原作者还未接受PR，目前仅可使用SYSJOINT分支版本）；
     NanoVNA-App_by_SYSJOINT下载地址：
     https://github.com/sysjoint-tek/NanoVNA-App/releases
     https://www.sysjoint.com/ueditor/php/upload/file/NanoVNA-App_by_SYSJOINT.zip
2、支持SVxx01A Tools上位机软件，可在PC端远程操作和演示SV6301A；
     SVxx01A Tools下载地址：https://www.sysjoint.com/ueditor/php/upload/file/SVXX01A_Tools.zip
3、校准件编辑功能优化：
     （a）完善校准件参数输入项；
     （b）支持科学计数法输入；
     （c）可编辑校准件名称；
     （d）可保存/回调校准件；
4、优化了S21直通阻抗测量；
5、优化了回调/保存校准文件界面；
6、优化了菜单和键盘输入；
7、新增vbat、capture串口命令以适配NanoVNA-App；
8、修复了一些BUG；