CXM539 User’s Manual
Doc.# 6001-0014 Rev1.2
Page 6
In run mode, most of the CXM539 parameters, e.g. baud rate, sample rate,
etc. can be set by the user. The main differences between the system
operation in run and configure mode are as follows:
1. The CXM539 can only be calibrated in config mode (by issuing
the l command). The unit is always factory calibrated and
recalibration by the user is not normally required.
2. The unit always starts in the (known) baud rate of 9600 baud.
3. The unit always starts in command mode (as opposed t o autosend
mode).
4. The data output format is selected to be A to D count mode.
The main functions of the config mode are to assure that the CXM539
communicates using a known baud rate (9600) and to enable calibration of
the system.
M
WARNING
Always operate the CXM539 in run mode (when using a terminal program)
unless the baud rate setting of the unit is unknown or calibration of the unit
is required. The output of the CXM539 in the calibrated mode (M=C) is
only valid in the run and auto modes.
4.2
System Checkout
After the CXM539 is operational and communicating with a computer, its
proper operation can be qualitatively checked out by using it to measure the
earth’s magnetic field. Around the globe, the magnitude of the earth’s
magnetic field varies from about 0.4 Gauss to 0.6 Gauss. In the northern
hemisphere, the field points north and dips into the ground (dip angle) at
about 60°.
Point the X axis generally north and down at an angle of 60° from
horizontal. Verify that the X axis reads about 0.5G and the Y and Z axis is
read near zero. Repeat the measurement with the Y and Z axes in turn
pointed into the field and verify that these two axes correctly read the
earth’s magnetic field magnitude.
If a terminal program is used before checking the system operation, ensure
that the following commands are given:
SUNSTAR传感与控制 http://www.sensor-ic.com/ TEL:0755-83376549 FAX:0755-83376182 E-MAIL:[email protected]
SUNSTAR自动化 http://www.sensor-ic.com/ TEL: 0755-83376489 FAX:0755-83376182 E-MAIL:[email protected]
