requests from clients. We define our TCP socket to
Hyper Terminal as shown in Screenshot 3.
At this point, we can connect to the i WEM-1001. Once
connected, we must select Properties from the File drop-down menu and select the Settings tab as shown in
Screenshot 4. This is where we define the terminal
emulation type. The ACE 2a wants to see a VT100 and
that’s what we’ll appear to be. A tap of the spacebar
results in Screenshot 5 which is the ACE 2a banner. We
have successfully contacted the ACE 2a via a TCP socket.
System Test
IP address range is not routable on the Internet. However,
you can use the 192.xxx.xxx.xxx address range in your
network behind the router. Most of today’s routers employ
NAT (Network Address Translation) functionality which
allows you to literally punch a hole in the router to allow
outside access to devices on the router’s 192.xxx.xxx.xxx
network. For instance, to put our i WEM-1001 configuration
on the Internet, we would use the router’s NAT
functionality to open an Internet access portal to TCP
socket 192.168.0.112:1000.
Whether you want to cut the wires locally via a LAN or
internationally via the Internet, the i WEM-1001 is a
foolproof and inexpensive way to go. SV
I wrote a small ALEC test program
and loaded it in Screenshot 6. The
ALEC code sets up the ACE 2a’s A-to-D
subsystem in line 10. A delay is
honored in line 20. Lines 30 and 40
push the current temperature to the
ACE 2a’s console. The temperature
data originates from an LM34. Upon
entering “run” into the Hyper Terminal
TCP socket session, ALEC compiles and
executes the temperature test
program.
Screenshot 7 is the result of
contacting the ACE 2a console,
loading a program, executing a
program, and viewing the results via a
wireless TCP socket connection.
The Possibilities
Besides telling me why it’s chilly in
here, this little demonstration can also
be used to tell me why it’s chilly in
Idaho. TCP sockets work on the
Internet just like they do in a lab
network contained within the confines
of a single room. All you have to do to
put the ACE 2a on the Internet is use
a routable address and designate a
local port address. The 192.xxx.xxx.xxx
Fred Eady can be reached via
email at fred@edtp.com.
Sources
IWEM-1001
Lemos International
www.lemosint.com
SPECTRUM ACE 2a
I2I Controls
www.i2icontrols.com
Li-Ion Battery Pack
Tenergy Corporation
www.tenergybattery.com
SERVO 06.2011 59
