East Coast Datacom MSD-4C User manual

TABLE OF CONTENTS
Page 74.0 - APPENDIX ......................................................
Page 63.6 ASCII STRING COMMANDS FOR SWITCHING . . . . . . . . . . . . . . . .
Page 63.5 MODEM (DCE) AND TERMINAL (DTE) CONNECTION . . . . . . . . . .
Page 63.4 DEFAULT CONFIGURATION SWITCH SETTINGS . . . . . . . . . . . . .
Page53.3 POWERCONNECTION ......................................
Page 53.2 VOLTAGE SELECTION FUSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Page53.1 VOLTAGESELECTION ......................................
Page 5CHAPTER 3 - INSTALLATION .........................................
......................................................................
........
Page 42.7 RS-232 SERIAL PORT CABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Page32.6 ANTI-STREAMING ..........................................
Page 32.5 SUB-CHANNEL SERVICE MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Page 22.4 RS-232 ASYNC ELECTRICAL INTERFACE . . . . . . . . . . . . . . . . . . . .
Page 22.3 ASYNC DATA RATES/CHARACTOR . . . . . . . . . . . . . . . . . . . . . . . . . .
Page 22.2 REAR PANEL CONNECTORS AND FUSES . . . . . . . . . . . . . . . . . . .
Page 22.1 FRONT PANEL INDICATORS AND SWITCHES . . . . . . . . . . . . . . . .
Page 2CHAPTER 2 - BASIC OPERATION .....................................
Page 21.2 THEORY OF OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Page 11.1 FUNCTIONAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Page 1CHAPTER 1 - INTRODUCTION ........................................
MSD-4C INSTALLATION AND OPERATIONS MANUAL

OPERATIONS MANUAL
4-Port RS-232
CODE OPERATED SWITCH
MSD-4C
November 1, 2010
Manufactured By :
East Coast Datacom, Inc.
Document
Number
201010 Rev-
FOR TECHNICAL SUPPORT CALL:
East Coast Datacom, Inc.
245 Gus Hipp Blvd., STE 3
Rockledge, FL 32955
TEL: [phone] or [phone]
FAX: [phone]
Email: [e-mail]
Web Address: www.ecdata.com

SAFETY WARNING
Always observe standard safety precautions during installation, operation and
maintenance of this product. To avoid the possibility of electrical shock, be sure to
disconnect the power cord from the power source before you remove the IEC power
fuses or perform any repairs.
PROPRIETARY NOTICE
The information contained herein is proprietary to East Coast Datacom, Inc. Any
reproduction or redistribution of this publication, in whole or in part, is expressly
prohibited unless written authorization is provided by East Coast Datacom, Inc.
WARRANTY NOTICE
WARRANTIES: East Coast Datacom, Inc. (hereafter referred to as E.C.D.) warrants
that its equipment is free from any defects in materials and workmanship. The warranty
period shall be three (3) years from the date of shipment. E.C.D.'s sole obligation
under its warranty is limited to the repair or replacement of defective equipment,
provided it is returned to E.C.D., transportation prepaid, within a reasonable period.
This warranty will not extend to equipment subjected to accident, misuse, alterations or
repair not made by E.C.D. or authorized by E.C.D. in writing.
PUBLICATION NOTICE
This manual has been compiled and checked for accuracy. The information in this
manual does not constitute a warranty of performance. E.C.D. reserves the right to
revise this publication and make changes from time to time in the content thereof.
E.C.D. assumes no liability for losses incurred as a result of out-of-date or incorrect
information contained in this manual.
MSD-4C INSTALLATION AND OPERATIONS MANUAL

CHAPTER 1 - INTRODUCTION
1.1 FUNCTIONAL DESCRIPTION
The MSD-4C is an asynchronous code-operated switch that has five RS-232 serial
ports consisting of a Master Port and four sub-channel ports. The user will enter an
ascii command from a computer that is transmitted over the Master port to the units
internal circuitry. The ASCII command automatically switches the Master Port data path
to one of the four sub-channel ports as specified in the ASCII command. The data path
is secure and does not allow the other data ports to access the Master Port until an
ASCII command is reissued.
Code-operated switches are useful in environments where remote switching is needed
for file-sharing or monitoring purposes. For example, you could use an RS-232 serial
code-operated switch to remotely switch between pieces of data terminal equipment
(DTE), such as servers or routers for running diagnostics from a remote console.
The MSD-4C operates in two primary modes of operation known as Text or Graphics.
1) In Text Mode, the unit will enter switch-time whenever it receives an arming
character. It will select the sub-channel that is specified by the channel select character.
The remaining text will pass through the unit until another arming character is
encountered.
2) The Graphics Mode is capable of passing graphics data while still maintaining code
control. In this mode, an arming character will only be recognized as an arming
character if it is preceded by a pause in data transmission of a minimum length of time.
The MSD-4C has status LED’s for the Master Ports control and data signals.
Additionally the unit has LED’s showing the sub-channel port connected. Internal
circuitry allows the user to select a time out of a data port. The time-out will allow other
data ports to then be accessed.
MSD-4C INSTALLATION AND OPERATIONS MANUAL
Page 1
TYPICAL APPLICATION
Figure 1.1

Located on the back or rear of the product you will find an IEC Power receptacle. The
supplied power cord plugs into this receptacle. This receptacle also contains a fuse
drawer. Two (2) fuses are located in this compartment. For 110 VAC +/- 10%
operation the unit is equipped with slow blow 160ma Fuses, Part # 714000. For 220
VAC +/- 10% operation the unit is equipped with slow blow 80ma Fuses, Part # 714001.
Additionally, you will find the Master Port and four sub-channel female DB-25
connectors.
2.3 ASYNC DATA RATES / CHARACTER
The MSD-4C has an internal Dip Switch to on the PCB to set data rates from the
internal baud rate switch located at SW-4. The unit supports ASYNC data rates in a
range from 1.2k up to 115.2k. The ASYNC character length is set at 8, N, 1 or 10 bit
data.
2.4 RS-232 ASYNC ELECTRICAL INTERFACE
The MSD-4C is EIA RS-232 (CCITT V.24) compliant using female DB-25 connectors.
All five RS-232 ports are configured as DCE(modem type) interfaces and connect to
A Green LED illuminates when AC Power has been applied and is marked PWR. Six
adjacent Green LEDs marked TXD, RXD, RTS, CTS, DTR, DCD illuminate in union
with the Master port control signal activity. Four adjacent green LED’s provide the user
with the active RS-232 sub-channel. Additionally, four yellow LEDs are provided to
provide the user with a visual indication of a streaming sub-channel(if enabled).
Positive latching switches are provided for each sub-channel port for isolating or
removing a sub-channel. Each sub-channel DTE port has its own switch and operates
independently. To disable a sub-channel simply push the switch. A channel is disabled
when the switch is in the outer most position.
2.2 REAR PANEL CONNECTORS AND FUSES
CHAPTER 2 - PRODUCT OVERVIEW
2.1 FRONT PANEL INDICATORS AND SWITCHES
1.2 THEORY OF OPERATION
A switch with a combination of input and output ports, the connections between which
can be remotely reconfigured by commands entered into a computer. Code-operated
switches are useful in environments where remote switching is needed for file-sharing
or monitoring purposes.
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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DTE(terminal type) equipment. Refer to the interface chart in the Appendix for detailed
interface information.
2.5 SUB-CHANNEL SERVICE MODES
The MSD-4C unit incorporates circuitry that enables the user to provide two separate
modes of DTE sub-channel access servicing. Either mode of operation is selected
upon installation via a Dip Switch located inside the housing located at SW1-4. The
user may select TEXT or GRAPHICS mode of operation.
2.5.1 TEXT MODE
In the Text Mode, the MSD-4C will enter switch-time whenever it receives an arming
character. It will select the sub-channel that is specified by the channel select ASCII
character. The remaining text will pass through the unit until another arming character is
encountered. The arming character and the sub-channel select character will not pass
through the unit in this mode. The user should make certain that the arming character
that will never appear as part of the text.
2.5.2 GRAPHICS MODE
The Graphics Mode is capable of passing graphics data while still maintaining code
control. In this mode, an arming character will only be recognized as an arming
character if it is preceded by a pause in data transmission of a minimum length of time
of 100 milliseconds of No Data.(other options available)
2.5.3 PASSED OR FORCED CONTROL SIGNALS
The MSD-4C has several user defined options for passing or forcing control signals.
Please refer to the Strap Chart in the Appendix.
2.6 ANTI-STREAMING
2.6.1 AUTOMATIC DTE REMOVAL
The MSD-4C incorporates circuitry that will (when enabled) automatically remove a
streaming sub-channel from service. A streaming terminal is defined as a terminal that
has been active longer than the user predefined anti-stream timer has been set. Upon
installation, the user can set or actually fine tune the timer to your network
requirements. Each channel has a Green and a Yellow LED to indicate sub-channel
activity. Green indicates an active sub-channel and Yellow indicates a streaming
sub-channel. Once a terminal has gone into the streaming condition (sub-channel
active too long) the DTE will automatically be removed from service until the DTE fault
has been corrected by the user. All other DTE's will continue to be serviced by the
MSD-4C.
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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2.7 RS-232 SERIAL PORT CABLES
The five ASYNC RS-232 female DB-25 sub-channel ports are configured as
DCE(modem type) interfaces for connection to DTE(terminal type) interfaces. The user
should use straight through cables for DCE to DTE connection. Since the MSD-4C is an
ASYNC device, the user may easily use crossover cables for DCE to DCE connection.
Please refer to the appendix for RS-232 pin outs and cabling information.
2.6.2 MANUAL DTE REMOVAL
The MSD-4C incorporates circuitry that will (when enabled) manually remove a
sub-channel from service. To disable a sub-channel simply push the switch. A
sub-channel is disabled when the switch is in the outer most position.
2.6.3 UNEXPLAINED STEAMING TERMINALS
Many different types of terminals have been manufactured over the years. A typical
problem is unexplained lockup or lockout problems. The most common cause is when,
four terminals are running just fine and when one of the terminals is powered down, the
remaining terminals are locked out of service. This may be explained by a missing or
incorrect Termination Resistor that has been overlooked by your terminal manufacturer.
This is the main reason that Anti-Streaming circuitry has been designed into the
MSD-4C and we encourage the user to take advantage of this feature.
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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Power Connection
Figure 3-1
CHAPTER 3 - INSTALLATION
3.1 VOLTAGE SELECTION
It is very important to check that the unit is set to the correct voltage setting for your
application before applying AC power. Located on the rear of the unit you will find a
rotary 110/220 VAC switch. Using a coin or small screwdriver, gently turn the switch to
the appropriate power position as required for your installation (110 or 220 VAC).
3.2 VOLTAGE SELECTION FUSES
Located on the back or rear of the product you will find an IEC Power receptacle. This
receptacle contains a fuse drawer. Two (2) fuses are located in this compartment. For
110 VAC +/- 10% operation the unit is equipped with slow blow 5 x 20mm 160ma
Fuses, E.C.D. Part # 714000. For 220 VAC +/- 10% operation the unit is equipped with
slow blow 5 x 20mm 80ma Fuses, E.C.D. Part # 714001. Spare fuses may be
purchased by calling East Coast Datacom or by calling the fuse manufacturer: Little
Fuse at [phone] or Schurter, Inc. at [phone]
Little Fuse Part #'s are: 160ma = 218.160 and 80ma = 218.080
Schurter, Inc. Part #'s are: 160ma = 034.3109 and 80ma = 034.3106
3.3 POWER CONNECTION
Before connecting the MSD-4C to an AC power source the top cover should be
installed with the supplied #6-32 screws. AC power is supplied to the MSD-4C through
a 2.3m (6.6 ft) cord terminated by a grounded 3-prong plug. Select an appropriate
location accessible to and within four to five feet of an AC outlet. The AC Power source
MUST be grounded or the MSD-4C warranty will be void.
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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CAUTION: Disconnect Power Before Servicing
ATTENTION: Couper Le Courant Avant l' Entretien
VORSICHT: Befor Deckung Abnehmen Mach Strom Zu

3.4 CONFIGURATION SWITCH SETTINGS
The MSD-4C is configured prior to shipping with the Dip Switches set as follows:
1) Anti-Streaming - Disabled
2) TEXT / GRAPHICS - TEXT Mode
3) Frame / Signal Ground - Not Connected
4) Control Signals - Passed straight
5) Data Rate - 9.6k
If your system application requires one or more of the default setting to be changed, it
will be necessary to remove the top cover of the MSD-4C. Remove the AC Power
source or Disconnect the AC Power before servicing the unit. Removal of the top
cover is accomplished by using a small Philips screwdriver and removing the four
outside screws. After setting the switches, replace the top cover before applying AC
power.
3.5 MODEM (DCE) AND TERMINAL (DTE) CONNECTION
Before applying AC Power to the unit, the DCE and DTE cabling should be connected.
Straight through Male to Male DB-25 shielded cables, no longer than 50 feet in any
direction should be used. If your cables are not shielded or over 50 feet long,
transmission errors are very likely.
3.6 ASCII STRING COMMANDS FOR SWITCHING
3.6.1 TEXT OR GRAPHICS MODE COMMANDS
When the user sets the MSD-4C in the Text Mode or Graphic Mode of operation, the
user commands issued from a computer to switch between the sub-channel ports are
the same for either mode. The ASCII control codes are send from the users computer
or embedded into the serial data stream as follows:
(Sub-Channel 1) Crtl D, 00
(Sub-Channel 2) Crtl D, 01
(Sub-Channel 3) Crtl D, 02
(Sub-Channel 4) Crtl D, 03
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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4.0 - APPENDIX
4.1 RS-232 DB-25 DCE PORT PIN OUTS(Same All Five Ports)
Below is a pin-out chart for the MSD-4C RS-232 DCE port pin-outs.
XData Terminal Ready (DTR)20
XData Carrier Detector (DCD)8
------Signal Ground (SG)7
XData Set Ready (DSR)6
XClear To Send (CTS)5
XRequest To Send (RTS)4
XTransmit Data (TXD)3
XReceive Data (RXD)2
------Shield (GND)1
To DCETo DTESignal DescriptionDB-25
Pin No.
4.2 STRAP CHARTS
OFFONOffOffOff
115200
ONOFFOnOffOff
76800
ONOFFOffOnOff
38400
ONOFFOnOnOff
19200
ONOFFOffOffOn
9600
ONOFFOnOffOn
4800
ONOFFOffOnOn
2400
ONOFFOnOnOn
1200
S3-2S3-1S1-1S1-2S1-3SPEED
OffXX
Disable
OnXX
Enable
OFFOFF
16 SEC
ONGRAPHICONOFF
8 SEC
OFFTEXTOFFON
4 SEC
ONON
2 SEC
S1-4
TEXT/GRAPHICS7-1S7-4S7-3
ANTI STREAM
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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CONTROL SIGNAL JUMPERS
CTS to Master is forced on
2 to 3
CTS to Master is from selected port's RTS
1 to 2
J11
CD to Master is forced on
2 to 3
CD to Master is from selected port's RTS
1 to 2
J10
CTS to Port 4 is forced
2 to 3
CTS to Port 4 is from Master DTR
1 to 2
J9
CTS to Port 4 is forced
2 to 3
CTS to Port 4 is from Master DTR
1 to 2
J8
CTS to Port 3 is forced
2 to 3
CTS to Port 3 is from Master DTR
1 to 2
J7
CD to Port 3 is forced on
2 to 3
CD to Port 3 is from Master RTS
1 to 2
J6
CTS to Port 2 is forced
2 to 3
CTS to Port 2 is from Master DTR
1 to 2
J5
CD to Port 2 is forced on
2 to 3
CD to Port 2 is from Master RTS
1 to 2
J4
CTS to Port 1 is forced
2 to 3
CTS to Port 1 is from Master DTR
1 to 2
J3
CD to Port 1 is forced on
2 to 3
CD to Port 1 is from Master RTS
1 to 2
J2
Signal ground and chassis gnd are connected
2 to 3
Signal ground and chassis gnd are isolated
1 to 2
J1
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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TEXT MODE ARMING CHARACTOR INFORMATION
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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GRAPHICS MODE ARMING CHARACTOR INFORMATION
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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Application
Code-operated switch allowing a user from a
computer to issue an ASCII code to switch the
data path routing data from the master port to
one of four sub-channel ports.
Capacity
One to four RS-232 ASYNC devices
Interface
EIA RS-232, CCITT V.24 using DB-25 female
connectors, +/- 15KV ESD Protection
Data Format
Asynchronous
Data Rates
1.2k, 2.4k, 4.8k, 9.6k, 19.2k, 38.4k, 76.8k,
115.2k
Modes of Operation
Text or Graphics
Anti-Streaming
Automatic . . .Selectable time out intervals
Disable . . . . .Selectable via dip switch
Front Panel
Indicators . . . Power, RTS, CTS, DCD, DTR,
TXD, RXD, Channel Active, Channel Stream
Switches . . . . Enable/Disable of each
Sub-channel
Power Source
100-120 to 200-220VAC @ 10%, 50/60Hz,
0.16/0.08A, external 110/220 volt select
switch, IEC Power Inlet, (2) 5mm Fuses
Regulatory Approvals Tested
According To
UL 60950-1:2003, CAN/CSA-C22.2 No.
60950-1:2003, CE Safety EN60950 and CE
EMC EN300-386-2
Environmental
Operating Temperature....32º to 122º F (0º to
50º C)
Relative Humidity.............5 to 95%
Non-Condensing
Altitude............................0 to 10,000 feet
RoHS Compliant
Yes, Lead Free
MTBF (Telcordia Issue 1)
601,386 hours
Dimensions
Height . . . 1.75 inches (4.44cm)
Width . . . . 17.00 inches (43.18 cm)
Length . . . .9.00 inches (22.86 cm)
Weight
MSD-4C ......... 4.5 pounds (2.1 Kg)
Warranty
Three Years, Return To Factory
ORDERING INFORMATION
Model: MSD-4C
Part Number: 201000
Description: 4-Port RS-232 Code-operated
Switch
INCLUDED WITH EACH UNIT:
1) Operations Manual
2) U.S.A. Grounded Power Cord, Part:713015
3) Optional Power Cords
A) United Kingdom, Part #713016
B) Continental Europe, Part #713017
C) Other: Specify Country on Purchase Order
For further detailed technical information on
this product, contact East Coast Datacom, Inc
at: [email protected]
MSD-4C INSTALLATION AND OPERATIONS MANUAL
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