28029 Parallax Inc, 28029 Datasheet - Page 133

• 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

Chapter 4: Hitachi HM55B Compass Module · Page 121
Schematic and Wiring Diagram
The HM55B can be connected with its Dout and Din pins tied together so that they
transmit and receive signals to and from the same BASIC Stamp I/O pin. Another
BASIC Stamp I/O pin is connected to the device's clock (CLK) pin. The BASIC Stamp
will send pulses to this pin as it makes the chip send its status or measurements or receive
commands. The BASIC Stamp also sends low signals to the Compass Module's /Enable
pin before it exchanges any data, and also to initialize each magnetic field measurement.
√
Build the circuit shown in Figure 4-3.
Figure 4-3: Compass Module Schematic and Wiring Diagram
Testing the Compass Module
This example program tests to make sure the compass module is connected properly and
in working order.
There may be sizeable differences between the magnetic north
reported by a mechanical compass and the one reported by the compass module. After
the calibration programs in upcoming activities, all apparent measurement errors should
disappear.
Figure 4-4 shows what the compass should display when it detects that it is facing 35°
clockwise of north. Again, don't worry about exact direction at this point because the
program is only testing to make sure the module is working. So long as you can use it to
get a general idea of north, south, east and west, it's in working order.