It’s possible to connect to serial console with MacOS without using a specific app but only screen.
First, you need to find the correct device you will use to connect to the serial console. Depending on your installation and your adapter, you’ll can find it under different names with one these commands:
$ ls /dev*/usb*
ls: /dev*/usb*: No such file or directory
$ ls /dev/tty*usb*
Here, we can see that our device is available on /dev/tty.usbserial
If you have any doubt with the screen command, you can check the documentation, with the specific part regarding the console connection:
If a tty (character special device) name (e.g. "/dev/ttya") is specified as the first parameter, then the window is directly connected to this device. This window type is similar to "screen cu -l /dev/ttya". Read and write access is required on the device node, an exclusive open is attempted on the node to mark the connection line as busy. An optional parameter is allowed consisting of a comma separated list of flags in the notation used by stty(1):
[1200,9600,19200] - First parameter is the baud rate
Usually 300, 1200, 9600 or 19200. This affects transmission as well as receive speed.
cs8 or cs7
Specify the transmission of eight (or seven) bits per byte.
ixon or -ixon
Enables (or disables) software flow-control (CTRL-S/CTRL-Q) for sending data.
ixoff or -ixon
Enables (or disables) software flow-control for receiving data.
istrip or -istrip
Clear (or keep) the eight bit in each received byte.
For example, if you want to connect to serial port with those parameters:
- 9600 bps
- 8 data bits
- flow control
You can just use this command:
$ screen /dev/tty.usbserial 9600,cs8,ixon
Hint: Note that if you’re using a specific adapter (like an adapter DB9/RS232 to USB), you will probably need to install the driver first to get the device available.