![Amazon.com: Your Cable Store RS232 DB9 9 Pin Serial Port Cable Female / Female (3 feet) : Electronics Amazon.com: Your Cable Store RS232 DB9 9 Pin Serial Port Cable Female / Female (3 feet) : Electronics](https://m.media-amazon.com/images/W/MEDIAX_792452-T2/images/I/51BciZYVs4L._AC_UF1000,1000_QL80_.jpg)
Amazon.com: Your Cable Store RS232 DB9 9 Pin Serial Port Cable Female / Female (3 feet) : Electronics
![Amazon.com: zdyCGTime 2 Port DB9 RS232Serial Port Bracket to 10 pin HeaderRibbon Cable Connector Adapter, DB9 Serial Male to 10P Motherboard Header Panel Mount Cable Serial Port Bracket (12in 4Pcs) (2 Port) : Electronics Amazon.com: zdyCGTime 2 Port DB9 RS232Serial Port Bracket to 10 pin HeaderRibbon Cable Connector Adapter, DB9 Serial Male to 10P Motherboard Header Panel Mount Cable Serial Port Bracket (12in 4Pcs) (2 Port) : Electronics](https://m.media-amazon.com/images/W/MEDIAX_792452-T2/images/I/41ARjYbMtAL._AC_UF350,350_QL80_.jpg)
Amazon.com: zdyCGTime 2 Port DB9 RS232Serial Port Bracket to 10 pin HeaderRibbon Cable Connector Adapter, DB9 Serial Male to 10P Motherboard Header Panel Mount Cable Serial Port Bracket (12in 4Pcs) (2 Port) : Electronics
![Amazon.com: USBGear 12 inch USB to Serial RS-232 DB-9 Pin Adapter with FTDI Chipset for Windows 10, 8, 7 and Mac Systems - Use for Laptop Serial Port, PDA, GPS, Modems, Routers and More : Electronics Amazon.com: USBGear 12 inch USB to Serial RS-232 DB-9 Pin Adapter with FTDI Chipset for Windows 10, 8, 7 and Mac Systems - Use for Laptop Serial Port, PDA, GPS, Modems, Routers and More : Electronics](https://m.media-amazon.com/images/W/MEDIAX_792452-T2/images/I/61c5OqbCvZL._AC_UF894,1000_QL80_.jpg)
Amazon.com: USBGear 12 inch USB to Serial RS-232 DB-9 Pin Adapter with FTDI Chipset for Windows 10, 8, 7 and Mac Systems - Use for Laptop Serial Port, PDA, GPS, Modems, Routers and More : Electronics
![rs232 - How can I use a serial port to listen to if a toggle is switched? - Electrical Engineering Stack Exchange rs232 - How can I use a serial port to listen to if a toggle is switched? - Electrical Engineering Stack Exchange](https://i.stack.imgur.com/kmUCx.png)