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© 2015 Active Research Limited
When connecting to a standard 9-pin RS232 serial PC
port, the cable and a connector must meet the following
specification:
1. A minimum of 3-cores are required in a shielded cable.
Higher quality cable will naturally yield higher performance/
higher Signal-to-Noise Ratio (SNR). Most typical cables
have two twisted pairs inside. In this case, use one pair for
the TX line and one for the RX line. Use the spare wire in
each pair as ground, and connect the cable shield to
ground only at the computer end.
2. A DB9 (9 pin D-type) type female (socket) connector for
the PC end of the cable.
3. The OUT +/A of the NGT-1 should be connected to the
RX of the computer (standard 9 pin D-type, pin 2) and the
NGT-1 IN +/A should be connected to the TX of the
computer (standard 9 pin D-type, pin 3).
4. Connect the IN -/B and OUT -/B together and connect to
the PC’s serial port ground (standard 9 pin D-type, pin 5).
Note:
To change the port number used in Windows refer
to
“Windows Port Number Configuration”
Note:
for LED
behaviour.
Note:
Actisense supply a cable with the 9 pin connector
already fitted, Actisense part ‘DB9-F’.
To fit the DB9-F cable refer to
Note:
The NGT-1-ISO PCB is labelled ‘NMEA 0183’ on
the RS232 side as the PCB shares the same design with
the
COMPUTER
NGT-1
Do not
connect
Personal
Computer
( 9 PIN 'D'
RS232
Port)
RX
Pin 2
GND
Pin 5
TX
Pin 3
Arrows indicate
direction of data flow
Figure 3 - PC / RS232 Port Connections
Connecting the ISO cable
On the ISO variants of the NGT-1, a pre-fitted four-core screened cable for connecting to a variety of devices. Actisense
ISO-Drive output circuitry and OPTO input circuitry allows many different types of device to be connected without the
need for configuration. Voltage levels are managed automatically as well as accepting both differential and ground
referenced connections safely. This allows connection to a standard RS232 PC port and the flexibility to connect to an
RS422 system if required for an embedded application.
“Table 2 - ISO Cable Connections”
shows the cable
assignments used.
Table 2 - ISO Cable Connections
Wire Colour
Wire Name
PCB Label
Connects To
Black
Opto In B / -
IN B / -
RS232 ground or RS422 OUT negative
Red
Opto In A / +
IN A / +
OUT positive
Blue
ISO Out B / -
OUT B / -
RS232 ground or RS422 IN negative
White
ISO Out A / +
OUT A / +
IN positive
Bare/Silver
Ground
ISO GND
Not Connected
Connecting to an RS232 (PC) port
Summary of Contents for NGT-1
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