Building Custom Cables
This section contains cabling information and how to build your own
custom cables for RocketPort controllers. To go to any of the following
topics, merely click on the topic:
• Building Custom Cables
• Shielding Cables
• Using Modular Connectors
• DTE to DCE Straight-Through Cables
• DTE to DTE Null-Modem Cables
• DTE to DTE Data-Only Null Modem Cables
• DTE to DTE Control Loop-Back Cables
• RS-422 DTE to DTE Cables
• Pinouts for DB25 Connectors
• Pinouts for DB9 Connectors
• Pinouts for RJ45 Connectors
• Pinouts for RJ11 Connectors
Building Custom Cables
Use this subsection if you want to build customized cables for the
Comtrol RocketPort controllers.
Usually you can buy the correct cables from distributors and electronics
stores for your controller. In some cases, your peripheral equipment
may need custom cables.
Check your equipment to understand what kind of cable to use, Data
Terminal Equipment (DTE) or Data Communications Equipment
(DCE). All Comtrol serial connectors are configured as DTE.
Building Custom Cables 1
Building Custom Cables
DTR
20
DTR
4
20
2
1 4
Shielding Cables
The controller falls within the limits for a Class A computing device
established by the FCC. To comply with these limits, the serial cables
used to connect the controller to external devices should be shielded.
The shield should be connected to a metal or metallized connector
shroud on each end of the cable.
Using Modular Connectors
The RJ45 and RJ11 connector is similar to the phone-jack type of
connector. Both the connector and cable are easily available from your
distributor or any electronics store. You may want to connect your
peripherals using a D-shell type of connector to an RJ45 interface with
a straight-through cable and an adapter that you build.
DTE to DCE Straight-Through Cables
The following figure shows the most common types of DTE to DCE
cables. This configuration also referred to as a modem cable, because
it works with most modems.
Note: If you have a DTE to DCE interface but are uncertain as to what
signals are needed, you can use a full 25-wire cable. This cable
is constructed like the following cable example, but in addition,
all of the remaining pins are connected
RocketPort Connector
DB25
RJ45
Signal
Name
TxD
RxD
RTS
CTS
DSR
GND
DCD
Pins
2
3
4
5
6
7
8
Pins
4
5
1
8
7
3
6
RJ11 DB9
Pins Pins
3 3
4 2
N/A 7
N/A 8
N/A 6
2 5
5 1
Remote Connector
DB9
DB25
Pins
2
3
4
5
6
7
8
Signal
Name
TxD
RxD
RTS
CTS
DSR
GND
DCD
Pins
3
2
7
8
6
5
1
DTE to DTE Null-Modem Cables
If you need RTS-CTS/DTR-DSR hardware flow control, you can
probably use the following figure. Some equipment may require
different connections for the control signals.
2 Building Custom Cables
Building Custom Cables
GND
7
GND
5
7
3
2 5
GND
7
GND
5
7
3
2 5
GND
7
GND
5
7
3
2 5
RocketPort Connector
Signal
Name
TxD
RxD
RTS
CTS
DSR
DCD
DTR
DB25
Pins
2
3
4
5
6
8
20
RJ45
Pins
4
5
1
8
7
6
2
RJ11 DB9
Pins Pins
3 3
4 2
N/A 7
N/A 8
N/A 6
5 1
1 4
Remote Connector
DB9
DB25
Pins
3
2
5
4
20
8
6
Signal
Name
RxD
TxD
CTS
RTS
DTR
DCD
DSR
Pins
2
3
8
7
4
1
6
DTE to DTE Data-Only Null Modem Cables
If no hardware flow is needed, use the following figure. With a 3-wire
cable, software flow control must be used, if control is needed.
RocketPort Connector
Signal
Name
TxD
RxD
DB25
RJ45
RJ11 DB9
Pins
Pins
2
3
Pins Pins
4
3 3
5
4 2
Remote Connector
DB9
DB25
Pins
3
2
Signal
Name
RxD
TxD
Pins
2
3
DTE to DTE Control Loop-Back Cables
Some equipment may not require hardware handshaking, but may
require that certain control signals are active before sending data.
RocketPort Connector
Signal
Name
Building Custom Cables 3
TxD
RxD
RTS
CTS
DSR
DCD
DTR
DB25
Pins
2
3
4
5
6
8
20
RJ45
Pins
4
5
1
8
7
6
2
RJ11 DB9
Pins Pins
3 3
4 2
N/A 7
N/A 8
N/A 6
5 1
1 4
Remote Connector
DB9
DB25
Pins
3
2
4
5
6
8
20
Signal
Name
RxD
TxD
RTS
CTS
DSR
DCD
DTR
Pins
2
3
7
8
6
1
4
Loading...