Serial Port

Very few workstations and laptops have serial ports, but they are still useful for connecting to network switches, routers, and servers.

I use a USB to Serial converter from Prolific Technology, Model PL2303 Serial. So far, I have not found anything which doesn't support it: Windows, Linux, even my Chromebook (with the Linux subsystem enabled) work just fine.

Most modern network devices use an RJ-45 connector. It looks like a network port, but it is wired as a serial port. HP has a cable with a DB-25 on one end (old school serial port) and an RJ-45 on the other, but that one generally sucks. Get one of the ones that Cisco has. Hint, it is normally light blue in color.

I plug the Cisco cable into my PL2303, the plug the other end of the Cisco into the device I want to control.

Following instructions are for a Chromebook, but should work similar for laptops or even a workstation.

1. On a Chromebook, enable the Linux subsystem
2. Download and install a serial communication software. I like minicom, others hate it and go with something else, but I'll describe minicom
3. Plug the USB to Serial device in. In my case, the first time, it asked if I wanted it available to ChomeOS or Linux, and I chose Linux
4. As root (sudo su), start minicom

   minicom -o -D /dev/ttyUSB0

   1. The -o says “don't initialize this as a modem”
   2. The -D sets the device (try

      ls /dev

      to find the device name

5. Configure minicom by pressing ^A-O
   1. Set baud to 9600 (to be safe)
   2. Set bits to 8N1
   3. Set hardware handshaking and software handshaking off
   4. exit, then save as default
6. Turn on the device (a network switch in my case)
7. If all goes well, you'll see the boot process start.