WS425 A/B NMEA Extended data message is as follows:
$P<id>MWV,<dir>,<ref>,<spd>,<uni>,<sta>*<chk><CR><LF>| $P | Fixed text |
| <id> | Data ID; A … Z |
| MWV | Fixed text |
| <dir> | Wind angle: 0 to 359 degrees |
| <ref> | Reference: R = relative |
| <spd> | Wind speed |
| <uni> | Wind speed unit: K = Kilometers per hour M = Meters per second N = Knots |
| <sta> | Status: A = Valid data V = Invalid data |
| * | Fixed text |
| <chk> | Checksum (8-bit XOR, excluding $ and *) |
| <CR> | Carriage return code, ASCII 0DH |
| <LF> | Line feed code, ASCII 0AH |
Missing readings
If data is missing due to a measurement problem, the NMEA messages show "V" in the status field. Wind speed and wind direction fields are left empty.