The idea is to use the Big Wire
(Internet) as a pipe to channel data to
and from a device using the well-worn
Internet protocols. If we can do the
same things to our device over the
Internet as we do with the device wired
in locally, the mission will be a success.
A server needs clients. Clients of
the type we’re looking for can be found
lying naked on an electronics bench or
embedded in a device attached to the
Big Wire. The only way to access our
clientele is to jump on that wire and
listen. We need only speak when
The Moray pictured in Photo 1 can
be accessed via its serial port, a Telnet
connection, or via a web-based HTTP
communications link. We will use the
Moray’s physical USB port to initially
prepare the Moray’s Numbat radio module for integration
into an in-house LAN.
The Moray’s serial port is based on an FTDI USB-to-serial IC. So, all we have to do is plug the Moray into
almost any PC’s host USB portal. If the PC is loaded with
the FTDI drivers, a virtual COM port will be spawned. To
use the newly born virtual COM port, we must make sure
that the host PC has a suitable terminal emulator program
installed. In our case, the host PC is running Windows 8.1,
which is supporting the necessary FTDI drivers and a copy
of the terminal emulator, Tera Term Pro.
The Moray’s default baud rate is 115200 bps. The
standard no parity, eight data bits, and one stop bit also
apply. If everything is set up correctly in Tera Term Pro,
after connecting the USB only a tap on the Enter key is
required to invoke a Ready prompt from the Moray.
The contents of Screenshot 1 contain the necessary
configuration variables to get the Moray
on the EDTP LAN. However, we haven’t
given the Moray enough network
information to make the WLAN info
stick. I’ve taken care of that in
Note that we are not using the
router’s DHCP server. Instead, we have
configured the Moray to use a static IP
address. The advantage to this is that
we never have to guess about what IP
address the Moray is operating against.
Knowing the IP address also allows us
to easily “open up” that IP address on
the router for use
as a server portal
on the Big Wire.
In that I know
everything about the
EDTP LAN, all of our
pay off. As you can
see in Screenshot 3, I was right. A save and reboot
operation resulted in an association of the Moray and the
EDTP LAN. This is good as it paves the way for a web
server to operate on the EDTP LAN.
At Your Service
The folks at ACKme have developed a really neat web
ADVANCED TECHNIQUES FOR DESIGN ENGINEERS
May 2015 69
■ Screenshot 1. All of the WLAN
configuration variables are
displayed here. We need only to
populate the variables that allow
us to join the local EDTP LAN.
Once on the LAN, we have access
to the Big Wire.
■ Screenshot 3. We are now on the “Little Wire,” which is otherwise known as
the EDTP LAN. The next step is to configure the Moray to operate as a web
server on this wire.
■ Screenshot 2. This screen capture
reveals the network configuration
variables necessary to allow the Moray
to join the EDTP LAN. Note that a static
IP configuration is used instead of
relying on DHCP to assign the network