HMR3500 User's Guide
declination and issue a DWMM message reporting the computed declination. The declination value is saved to the
compass' non-volatile memory and is used by the compass as the current declination value when computing azimuth.
The current magnetic declination is displayed in the Initialization dialog box (see Figure 7). To perform the calculation,
issue a WMM message. Because the calculations are extensive, the compass performs them in background mode, but
the calculated declination will be posted, and reported in a DWMM message, about one-half second later.
Request Data: 15 bytes:
The Day, Month, Year and Lat, Lon, Alt fields contain the date and position information needed by the World Magnetic
Reply Data: 23 bytes:
Version Name: VRSN/DVRSN
Request Data: None
Day of month [1..31]
Month of year [1.12]
Year – 2000
0 = calculation inhibited
1 = calculation completed and posted
2 = calculation in process
3 = awaiting date and/or location
4 = flash write failure
Current variation (declination).
Name of USGS file from which model was derived (null
Major firmware version number
Minor firmware version number
Firmware builds options as individual bit flags. Contact Honeywell for
This unit's serial number.