NSF node

Setup:

launch host with:

pppd -detach crtscts lock proxyarp <local IP>:<remote IP> /dev/ttyUSB1 921600

launch client with:

sudo pppd -detach crtscts lock defaultroute noauth <local IP>:<remote IP> /dev/ttyO1 921600

make sure IP forwarding is enabled on the host:

sysctl -w net.ipv4.ip_forward=1
cat /proc/sys/net/ipv4/ip_forward

Impulse pin numbers from the micromodem implementation doc.

pin	color	impulse	breakout color	ftdi color
com1rx	yellow	1	black	orange
com1tx	green	3	red	yellow
com2tx	orange	2	white	yellow
com2rx	blue	4	green	orange
com2cts	grey	5	orange	green
com2rts	purple	6	yellow	brown
v+	red	7	brown	nc
gnd	black	8	blue	black