`Makefile.slip` assumes use of a SAMR21 Xplained Pro. This file describes how we use the board as a border router. See the [SLIP instructions][1] for the gnrc_border_router example for more background.
## Background -- Building
Build commands, for reference:
make clean BOARD="samr21-xpro"
# Use -f only for border router!
make -f Makefile.slip BOARD="samr21-xpro"
../../dist/tools/usb-serial/list-ttys.sh
# Use -f only for border router!
make -f Makefile.slip flash BOARD="samr21-xpro" SERIAL="???"
make term BOARD="samr21-xpro" PORT="/dev/ttyACM???"
## USB serial port
The USB serial port requires a USB-TTL converter cable with 3.3 V output.
Pin connections for SAMR21 board:
* PA23 (RX) -- TXD wire
* PA22 (TX) -- RXD wire
* GND -- GND wire
## Network configuration
We will define two networks:
1.`bbbb` Between Border Router (BR) and Ubuntu host over TUN
2.`aaaa` Between RIOT router node and BR over 6LoWPAN
We include two approaches to configuration below, automated via RPL, and manual via fib.
First, define a TUN interface on an Ubuntu host with tunslip, in the `dist/tools/tunslip` directory. In the example below, the tun interface is host 1.
cd ../../dist/tools/tunslip/
sudo ./tunslip6 -s ttyUSB0 -t tun0 bbbb::1/64
sudo ip -6 route add aaaa::/64 dev tun0
### RPL-based configuration
Configure the interface to the `bbbb` network on the BR from the RIOT terminal. The example commands below assume SLIP is on interface 8.
# Set address for SLIP interface
ifconfig 8 add unicast bbbb::2/64
# Add the Ubuntu host to the neighbor cache
ncache add 8 bbbb::1
Next configure the interface for the `aaaa` network on the BR. Strictly speaking, it is not necessary to define this address. However, it is convenient for typing, because RIOT automatically creates a more verbose address based on the MAC address for the interface.
ifconfig 7 add unicast aaaa::1/64
rpl init 7
Next, configure the interface on the `aaaa` network on the RIOT router mote.
ifconfig 7 add unicast aaaa::2/64
rpl init 7
Finally, set the BR as the RPL DAG root.
rpl root 1 aaaa::1
Ping the TUN interface from the router mote, via the BR:
