diff --git a/bbn_m5atomS3_lite_env3/NmeaXDR.h b/bbn_m5atomS3_lite_env3/NmeaXDR.h
new file mode 100644
index 0000000..fb34379
--- /dev/null
+++ b/bbn_m5atomS3_lite_env3/NmeaXDR.h
@@ -0,0 +1,75 @@
+#ifndef NmeaXDR_h
+#define NmeaXDR_h
+
+/*
+  XDR - Transducer Measurement
+  https://gpsd.gitlab.io/gpsd/NMEA.html#_xdr_transducer_measurement
+  https://www.eye4software.com/hydromagic/documentation/articles-and-howtos/handling-nmea0183-xdr/
+
+  Format: $--XDR,a,x.x,a,c--c, ..... *hh<CR><LF>
+  Example:
+
+  $HCXDR,A,171,D,PITCH,A,-37,D,ROLL,G,367,,MAGX,G,2420,,MAGY,G,-8984,,MAGZ*41
+  $SDXDR,C,23.15,C,WTHI*70
+
+  Transducer Types:
+     A - Angular displacement
+     C - Temperature
+     D - Depth
+     F - Frequency
+     H - Humidity
+     N - Force
+     P - Pressure
+     R - Flow
+     B - Absolute humidity
+     G - Generic
+     I - Current
+     L - Salinity
+     S - Switch, valve
+     T - Tachometer
+     U - Voltage
+     V - Volume
+     could be more
+
+  Unit of measurement                                     
+     "" - could be empty!                                 
+     A - Amperes                                          
+     B - Bars | Binary                                    
+     C - Celsius                                          
+     D - Degrees                                          
+     H - Hertz                                            
+     I - liters/second                                    
+     K - Kelvin | Density, kg/m3 kilogram per cubic metre 
+     M - Meters | Cubic Meters (m3)                       
+     N - Newton                                           
+     P - Percent of full range | Pascal                   
+     R - RPM                                              
+     S - Parts per thousand                               
+     V - Volts                                            
+     could be more
+*/
+
+/*
+  Bareboat Necessities Sensors NMEA-0183 XDR Sentences:
+
+  NMEA-0183 Sender 
+    BB
+
+  Temperature, pressure, humidity
+
+  $BBXDR,C,28.07,C,TEMP*61
+  $BBXDR,P,101328.38,P,PRES*76
+  $BBXDR,H,44.57,P,HUMI*63
+
+*/
+
+#include "NmeaChecksum.h"
+
+void gen_nmea0183_xdr(const char *nmea_fmt, float value) {
+  char nmea_part[82];
+  snprintf(nmea_part, 76, nmea_fmt, value);
+  int checksum = nmea0183_checksum(nmea_part);
+  Serial.printf("%s*%02X\r\n", nmea_part, checksum);
+}
+
+#endif