Finding the USB TTY Device#
On most distributions the device we want to connect is
/dev/ttyUSB1. You can verify where the two FTDI USB Serial USB Device converters ended up by running
dmesg after connecting your GRiSP board.
On macOS you can list the USB serial devices like this:
$ ls /dev/*usb* /dev/cu.usbserial-001030 /dev/tty.usbserial-001030 /dev/cu.usbserial-001031 /dev/tty.usbserial-001031
We want the TTY devices, and specifically the second one (the first is the debugging interface). In this example the serial number of the GRiSP board is
0103, and the device we want is
To connect we use
$ screen <device> 115200
<device> is the full path to the device discovered above and
115200 is the baud rate we need to use.
screen is quite handy because it literally runs everywhere a nice commercial alternative on Mac OSX is Serial.app
Some distributions require you to run
sudo. Some distributions require users to be in the
dialaut system group.
There is still a bug which prevents typed text from appearing in the Erlang shell until you press enter. At the moment you will have to work "blind" when tying characters or connect over the network. Having a Editor buffer ready from where Erlang command-lines can be cut&pasted is also handy.
Also Serial.app has a
Echo typed characters option in its Terminal Settings (Terminal -> Settings... -> Terminal Settings) which helps a lot unless the bug is fixed.
We are moving towards the termios driver from FreeBSD instead of the RTEMS built in one which will have no such issue.