Nuts and Volts - February 2013

DESIGN CYCLE

■ SCREENSHOT 1. This test is kinda like bucking physics. When gravity doesn't work the way you know it should, you're probably not on Earth.

■ SCREENSHOT 2.

This get ip command was issued from that Telnet session we invoked in Screenshot 1. We now have total control.

for both TCP and UDP operation.

Linksys router:

INITIAL RN-XV SETUP

I moved the RN-XV back to the carrier so I could configure it using a serial-based Tera Term session. Once we’ve given the RN-XV enough configuration information to go wireless, I’ll move it back to the “Rabbit” hole.

Let’s take care of the IP setup first. After starting the Tera Term serial session, entering transfers us from data mode to command mode. The

So, let’s turn DHCP off:

set ip address 192.168.0.88
AOK
<2.36> set ip gateway
 192.168.0.1
AOK

The < 2. 36> prompt reflects the version of the RN-XV’s firmware. The RN-XV’s local port number is next on our list of configuration parameters: I think you’ve got the idea. So, we’ll force the RN-XV to use DNS by configuring the TCPMODE parameter. I’ll go ahead and set up some of the other IP configuration parameters, and then we’ll take a look at what we’ve done in the IP area so far:

<2.36> set ip
 localport 8888
AOK
<2.36> set ip
 tcp-mode 0x4
AOK
<2.36> get ip
IF=UP
DHCP=OFF
IP=192.168.0.88:8888
NM=255.255.255.0
GW=192.168.0.1

■ SCHEMATIC 3.
Definition of an LMX-
ISM-242-LR: One 100
mW radio, one 12 MIPs
microcontroller, and a
regulated power
supply all on a
single piece of
copperclad
fiberglass.