DMR File

All odometer data must be written into Waypoint’s generic format (DMR) before it can be used within Inertial Explorer.

DMR Header Struct Definition

Word

Size

Type

Description

szHdr

8

char[8]

“$DMIRAW\0” – NULL terminated ASCII string

sHdrSize

2

int16_t

Size of the header in bytes, must be set to 512

sRecSize

2

int16_t

Size of each record (refer to dmi_lrec_type or dmi_drec_type)

12 + 8 if sValueType = DMI_VALUE_DOUBLE

12 + 4 if sValueType = DMI_VALUE_LONG

sValueType

2

int16_t

0 = logging data using 4 byte integer values

1 = logging data using double precision values

sMeasType

2

int16_t

1 = logging a distance measurement

2 = logging a speed measurement

sDim

2

int16_t

Number of DMI sensors.

Supports up to 3 wheel sensors, but the software applies DMI updates from the first wheel sensor only.

sRes

2

int16_t

Measurement resolution of the DMI

1 = low resolution, measurements on full wheel revolutions

2 = high resolution, measurements on partial wheel revolutions or fixed time intervals

sDistanceType

2

int16_t

Must be set if sMeasType == 1

1 = logging accumulated tick count

2 = logging distance in meters

3 = logging accumulated distance in meters

sVelocityType

2

int16_t

Must be set if sMeasType == 2

1 = logging velocity in meters/second

2 = logging velocity in ticks/second

dScale

8

double

DMI scale factor in meters/count or meters/second/count.

Must be set if SValueType == 0

1.0 if logging accumulated tick count or ticks/second

szAxisName

48

char[3][16]

Name of axes of each DMI. Optional

dWheelSize

8

double

Circumference of the wheel sensor in meters. Must be set if logging accumulated tick count

lTicksPerRevolution

4

int32_t

Number of tick counts per revolution of the wheel sensor. Must be set if logging accumulated tick count or ticks/second

cExtra2

420

int8_t[420]

Reserved for future use

The single header, which is a total of 512 bytes, is followed by one of the following structure types for each DMI measurement record:

DMR Long Record Struct Definition

Word

Size

Type

Definition

sSync

2

int16_t

Sync byte, 0xFFEE

sWeek

2

int16_t

GPS week number, set to -1 if unknown

dTime

8

double

GPS seconds into week

lValue

4 x sDim

uint32_t

Value for DMI sensor as an integer.

DMR Double Record Struct Definition

Word

Size

Type

Description

sSync

2

int16_t

Sync byte, 0xFFEE

sWeek

2

int16_t

GPS week number, set to -1 if unknown

dTime

8

double

GPS seconds into week

dValue

8 x sDim

double

Value for DMI sensor as a double.