900240 Rev. B
3/01
page 1
1.0
INTRODUCTION
Thank you for purchasing Honeywell’s HMR3000 Digital Compass Module. The HMR3000 uses Honeywell magnetic
sensors with proven MR technology and a two-axis tilt sensor to bring you the heading information. This electronically
gimbaled compass gives accurate heading even when the compass is tilted up to 40 degrees. The HMR3000 is reliable
and rugged since it does not contain any moving components and uses all surface mountable components. This low
power, small device is housed in a non-magnetic metallic enclosure that can be easily installed on any platform.
The HMR3000 is easy to use and extremely versatile. It allows the user to configure compass output to include any
combination of six NMEA standard messages and to change measurement parameters for the magnetometer to suit the
application. The sophisticated auto compass calibration routines will correct for the magnetic effects of the platform.
Wide dynamic range of the magnetometer (
±
1 G or 100
µ
T) allows the HMR3000 to be useful in applications with large
local magnetic fields.
2.0
GETTING TO KNOW THE HMR3000 PRODUCT
2.1
Identifying the product
HMR3000 Compass module comes in three different options:
(1) Circuit board with RS 232 or RS485 electrical interface
(2) Housed Compass Module with RS232 or RS485 electrical interface
(3) Demonstration Kit (RS232 only)
The electrical interface of the compass module is clearly marked on the circuit board in option (1) and on the product
label in option (2). Option (3) only comes with RS232 electrical interface.
2.2
Setting up
Interface and power cables—
Interface and power supply should be included in the Demonstration Kit (see
Electrical
Connections
in Section 2.4).
For other HMR3000 product options, a cable having a standard 9-pin D shell female connector should be wired
according to the pin-out defined below. Power should only be connected to
either
pin 9
or
pin 8. It is sufficient to
connect the pins listed in Table 1 for most applications. However, pins 1, 4, 6 and 7 serve specific purposes in the
operation of HMR3000 and should be kept open (high logic state) in normal operation (see Table 2
for complete pin out
description). See Figure 1 for suggested cabling diagram for connection between HMR3000 and COM port of a
computer (IBM).
Name
In/Out
Pin
Description
TxD / A
Out
2
RS-232 transmit out / RS-485 transmit-receive signal
RxD / B
In
3
RS-232 receive in / RS-485 transmit-receive return
GND
In
5
Power and signal common
6-15V
In
9
Unregulated power input
5V
In
8
Regulated power input
Table 1. Pin assignment for typical operation of HMR3000
(See Table 2 for complete description)
Caution: Do NOT 5.5V at regulated power input (pin 8). Higher voltages will damage components.