You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
71 lines
1.6 KiB
Go
71 lines
1.6 KiB
Go
package lc
|
|
|
|
import (
|
|
"fmt"
|
|
|
|
dmr "github.com/pd0mz/go-dmr"
|
|
)
|
|
|
|
// Data Format
|
|
// ref: ETSI TS 102 361-2 7.2.18
|
|
const (
|
|
ErrorLT2m uint8 = iota
|
|
ErrorLT20m
|
|
ErrorLT200m
|
|
ErrorLT2km
|
|
ErrorLT20km
|
|
ErrorLE200km
|
|
ErrorGT200km
|
|
ErrorUnknown
|
|
)
|
|
|
|
// PositionErrorName is a map of position error to string.
|
|
var PositionErrorName = map[uint8]string{
|
|
ErrorLT2m: "< 2m",
|
|
ErrorLT20m: "< 20m",
|
|
ErrorLT200m: "< 200m",
|
|
ErrorLT2km: "< 2km",
|
|
ErrorLT20km: "< 20km",
|
|
ErrorLE200km: "<= 200km",
|
|
ErrorGT200km: "> 200km",
|
|
ErrorUnknown: "unknown",
|
|
}
|
|
|
|
// GpsInfoPDU Conforms to ETSI TS 102 361-2 7.1.1.3
|
|
type GpsInfoPDU struct {
|
|
PositionError uint8
|
|
Longitude uint32
|
|
Latitude uint32
|
|
}
|
|
|
|
// ParseGpsInfoPDU parse gps info pdu
|
|
func ParseGpsInfoPDU(data []byte) (*GpsInfoPDU, error) {
|
|
if len(data) != 7 {
|
|
return nil, fmt.Errorf("dmr/lc/talkeralias: expected 7 bytes, got %d", len(data))
|
|
}
|
|
|
|
return &GpsInfoPDU{
|
|
PositionError: (data[0] & dmr.B00001110) >> 1,
|
|
Longitude: uint32(data[0]&dmr.B00000001)<<24 | uint32(data[1])<<16 | uint32(data[2])<<8 | uint32(data[3]),
|
|
Latitude: uint32(data[4])<<16 | uint32(data[5])<<8 | uint32(data[6]),
|
|
}, nil
|
|
}
|
|
|
|
// Bytes returns GpsInfoPDU as bytes
|
|
func (g *GpsInfoPDU) Bytes() []byte {
|
|
return []byte{
|
|
uint8((g.PositionError&dmr.B00000111)<<1) | uint8((g.Longitude>>24)&dmr.B00000001),
|
|
uint8(g.Longitude >> 16),
|
|
uint8(g.Longitude >> 8),
|
|
uint8(g.Longitude),
|
|
uint8(g.Latitude >> 16),
|
|
uint8(g.Latitude >> 8),
|
|
uint8(g.Latitude),
|
|
}
|
|
}
|
|
|
|
func (g *GpsInfoPDU) String() string {
|
|
return fmt.Sprintf("GpsInfo: [ error: %s lon: %d lat: %d ]",
|
|
PositionErrorName[g.PositionError], g.Longitude, g.Latitude)
|
|
}
|