Console connection to EL-16

I’m trying to establish a connection to a Digi-term EL-16 via port 1 in accordance with the following instructions:

Activating the Boot Console
Serial Cable required: To gain access to the Boot Console, you will need to attach a terminal or terminal emulator to Port 1 of the Etherlite.
A three-wire cable is used, which connects TXD, RXD, and GND (the Etherlite does not assert DTR or RTS by default). If your terminal requires these signals, you will need to loop them at the terminal side.
The Boot Console operates at 19200 baud, 8 data bits, 1 stop bit, and No Parity.
To activate the console:
Unplug the Ethernet cable from the Etherlite.
Plug (or unplug/re-plug) the power into the Etherlite. The Link LED should be off and the Power LED flashing. If Link LED is still lit, see #1 above.
On the terminal keyboard, press the # key repeatedly until you get a console prompt (should only take 3 strokes). If prompt is not seen, verify the correct serial settings are in use on the terminal, as described above.

That information came from this link:

I tried multiple baud rates and multiple console cables but no dice. I made sure to drop the LAN cable and power cycled multiple times.

I can’t figure how what “press the # key” means. What is the “#” key?