Wi-Fi Wireless

1
Wi-Fi Wireless Telescope Computer Interface
by Monroe Pattillo President, SFAAA
2
Goals
Eliminate cable between computer and
scope Remove nighttime trip hazard of
cable Reduce scope setup/teardown
times Identify generic, standards based
solution Validate solution with existing
equipment Document and disseminate solution to
others
3
Telescope Computer Interface
Serial (not parallel) Asynchronous (not char. or
bit synchronous) RS-232 (TIA/EIA-232E) 9600
bps, no parity, 1 stop bit No handshake (not
hardware, not software) Classical three wire
interface (TxD, RxD, Gnd)
4
Standards Based Wireless Technology Choices
Wi-Fi (chosen for this validation) flexible
range, addressing, Internet routing - larger,
more expense, more power Bluetooth (previous
solution validation) small, inexpensive, low
power - addessing, short range, no Internet
routing
5
Wi-Fi Product Selection Criteria
Wi-Fi IEEE 802.11b (compatible w/802.11g) Support
s TCP/IP tunneling and web server External power
(doesnt use interface power) Product open
information and availability Product adaptable
to telescope control
6
Wi-Fi Application/Protocol Layers
Wi-Fi 802.11b Serial Device Adapter
PC or PDA
Wi-Fi 802.11b 2.4GHz Wireless
Ethernet Interface
Ethernet Interface
IP Protocol
Wired Interface, Wireless Access Point,
Wireless Router, or Internet
IP Protocol
TCP Client
TCP Server
RS-232 Port
Telescope Application
Virtual COM Port Driver
7
Quatech ABSE-100D
IEEE 802.11b, TCP/IP tunnel, web server
config Removable ant, Indicators, Mounting
sleeve Captive serial cable, Includes AC-DC
adapter Product adaptable to telescope control
8
Adapting the ABSE-100D to Meade 8 LX-200 Classic
Adapt ABSE-100D DB-9M to LX-200s RJ-14 Need
simple, easy to reproduce solution Need to dress
it neatly to the LX-200 Sol RJ-11 to RJ-45 to
DB-9 to ABSE-100D 1 ft telephone cord and
RJ-45/DB-9 adapter Velcro ABSE-100D to side of
LX-200
9
Wiring for the unmodified telephone crossover cord
Unmodified End Black, Red, Green, Yellow
Unmodified End Yellow, Green, Red, Black
Y
G
B
R
B
R
G
Y
Just an unmodified standard crossover phone
cord Use a stranded wire cord, not silver satin
(foil over plastic)
10
Wi-Fi on PC
You need Wi-Fi IEEE 802.11b (or g) on
PC Built-in, USB, or PCMCIA/CardBus Discover
ABSE-100D, configure via web Set it to known IP
address and port number Install VCOM software (or
its equivalent) Establish virtual COM port (TCP
port tunnel) Try to set PC virtual COM port to
COM1..4 DPAC VCOM vs Lantronix COM port redirector
11
The Solution
ABSE-100D Velcro mounted and wire tied to the
side of Meade LX-200 Classic
(clear of fork arm movement)
The Wi-Fi antenna can be tilted outward and
rotated as needed or an extension cable can be
used to relocate or to upgrade the antenna
12
Operation
Mount and connect solution to telescope Connect
power to ABSE-100D Establish Wi-Fi
network Connect PC to IP network to Wi-Fi
network Connect PC virtual COM port to
ABSE-100D Launch telescope control application
on PC Enable telescope interface to virtual COM
port
13
Contact Information
Quatech ABSE-100D www.quatech.com Lantronix COM
port redirector www.lantronix.com Monroe
Pattillo President South Florida Amateur
Astronomers Association, Inc. (SFAAA) www.sfaaa.co
m Fox Observatory, inside Markham Park Open to
public Saturday evenings til midnight NW corner
of I-75-N/I-595 and FL-869/I-75-S
14
Other Projects
Previous Project Created wireless solution based
upon Bluetooth Slightly lower cost, smaller pkg
size than Wi-Fi
Next Projects Create a poor mans
StellarCam Windows PC based application and
server Source agnostic (video, webcam,
files) Format agnostic (BMP, JPEG, TIFF) Stack
and adjust images as they arrive Result image
accessed via web browser Create Wi-Fi based
control and imaging solution Wired Ethernet
Servers - RS-232 Video Concentration - Wired
Ethernet to Wi-Fi