28029 Parallax Inc, 28029 Datasheet - Page 137

• Manufacturer Part Number: 28029
• Description: KIT PARTS SMART SENSORS W/TEXT
• Manufacturer: Parallax Inc

Specifications of 28029

• Accessory Type: Parts Kit
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: BASIC Stamp® or Javelin Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant
• Other names: 28029PAR

The compass module can also sense magnetic fields from magnets, but magnets can also
damage the sensor! BE CAREFUL!
√
√
√
Find a total magnetic field intensity map that shows your locale, and then use it
to calculate the x-axis magnetic field intensity units for your compass module. If
the total magnetic field intensity was listed in nanoteslas, then your result will be
in nanoteslas per x-axis unit. To convert to microteslas, divide your result by
1000.
Start by setting your board on a table and lining up its x-axis with magnetic
north.
Hold a bar magnet above the compass module with its S pole pointing north and
its N pole pointing south as shown in Figure 4-5. Start from 1 m above, and
lower it until the Debug Terminal reports an x-axis reading of 120.
x
Do not place powerful magnets close to the compass module!
Keep bar, horseshoe, and electro magnets well away from your compass module until you
have determined a safe distance using the procedure below. Make sure not to ever place
them close enough to cause x or y-axis readings larger than ±300, because it could damage
the module.
axis
units
=
total
magnetic
x
axis
reading
Chapter 4: Hitachi HM55B Compass Module · Page 125
field
intensity