![COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center](https://support.arduino.cc/hc/article_attachments/360016532000/COM_port_changes_2.png)
COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center
StarTech.com 1-Port PCI Express RS232 Serial Adapter Card - PCIe Serial DB9 Controller - Low Profile - PEX1S953LP - Serial Adapters - CDW.com
![Serial Port Control - Easy to use control intended for simplification serial port communication tasks in your projects. Serial Port Control - Easy to use control intended for simplification serial port communication tasks in your projects.](http://www.serial-port-control.com/img/products/spc/spc-example.gif)
Serial Port Control - Easy to use control intended for simplification serial port communication tasks in your projects.
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