MicroStrain Inertia-Link 3DM-GX2 Specification sheet

Technical Note
Inertia-Link®
3DM-GX2®
Orientation Sensors
Interfacing with Other RS-422 Devices
Overview
MicroStrain’s Inertia-Link®and 3DM-GX2®can be outfitted with an RS-422 communications
interface. There is no standard for connector pin compatibility between RS-422 devices made by
different vendors. This technical note presents an example of how the Inertia-Link®and 3DM-
GX2®can be interfaced to another vendor’s device.
Pin Assignments
The Inertia-Link®and 3DM-GX2®present a female Micro-D 9-pin connector on the sidewall of
the enclosure. This connector provides the communications and power interface to the devices.
The pin layout as viewed from outside the enclosure is shown in the following figure:
Figure 1
The connector pin assignments are described in the following table and notes:
Pin # RS422
1 -
2 -
3 +5V
1
4 RxD+
2
5 RxD-
2
6 +6V/+9V/+12V
1
7 TxD+
2
8 GND
9 TxD-
2
Table 1

Interfacing with Other RS-422 Devices
Notes:
1Connect either pin 3 or pin 6 (no need to connect both).
Pin 3 voltage allowable range is +4.5V to +5.5V.
Pin 6 voltage allowable range is +5.2V to +16V.
Use whichever is more convenient.
2RxD is the node’s receive pin, and should be connected to the host’s transmit pin.
TxD is the node’s transmit pin, and should be connected to the host’s receive pin.
A mating male Micro-D 9-pin connector can be acquired from Ulti-Mate Connector, Inc.
www.umi-c.com part number PR9N05-26 or PR9N05-26E5-4.0.
SEALEVEL®Systems Incorporated, Liberty, South Carolina, USA http://www.sealevel.com
manufactures the Model 7204-SE Ultra-COMM+2 4.22 PCI Serial Interface board
http://www.sealevel.com/product_detail.asp?product_id=691 .
The connector pin assignments for the RS-422 interface are described in the following table:
Signal Name Pin# Mode
GND Ground 5 -
TX+ Transmit Data Positive 4 Output
TX- Transmit Data Negative 3 Output
RTS+ Request To Send Positive 6 Output
RTS- Request To Send Negative 7 Output
RX+ Receive Data Positive 1 Input
RX- Receive Data Negative 2 Input
CTS+ Clear To Send Positive 9 Input
CTS- Clear To Send Negative 8 Input
Table 2
Communication Connection
The connector pin assignments from the Inertia-Link®and 3DM-GX2®to the SEALEVEL® are
described in the following table. Please note the Tx and Rx cross-over.
Inertia-Link®/3DM-GX2®SEALEVEL®
Pin # Pin #
4 4
5 3
7 1
8 5
9 2
Table 3
Power
In our example we are only dealing with the communication connection; the SEALEVEL® board
does not provide power to the Inertia-Link®and 3DM-GX2®; power must be provided through
the standard MicroStrain cable or through user-designed means.
MicroStrain, Inc.
310 Hurricane Lane, Unit 4 ph: 800-449-3878
Williston, VT 05495 USA fax: [phone]
Copyright © 2008 MicroStrain, Inc. www.microstrain.com [email protected]