PPP

To make a PPP link over a radio modem or serial cross-over cable:

first make sure there is no getty running on your serial port (if there is edit /etc/inittab)

Gumstix can run a server for Laptop on ttyS2:

/usr/sbin/pppd /dev/ttyS2 38400

the other side runs the same thing but with its own tty

Put the following options in /etc/ppp/options/ttyS2: noauth persist passive silent lcp-echo-failure 3 lcp-echo-interval 5 (as that avoids a long commandline) For a radio-modem link the /etc/ppp config files were configured as follows:

Refstation PPP options:

9600
lock
local
passive
noauth
persist
silent
lcp-echo-failure 3
lcp-echo-interval 5

Base PPP options:

9600
lock
local
noauth
demand
connect /bin/true
lcp-echo-failure 3
lcp-echo-interval 5
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