From 35831b2d5a49c6900267ab5ea74077a6a2e57d64 Mon Sep 17 00:00:00 2001
From: Mikhail Grushinskiy <mgrouch@users.noreply.github.com>
Date: Wed, 13 Nov 2024 17:36:35 -0500
Subject: [PATCH] Add files via upload

---
 .../NmeaChecksum.h                            | 23 ++++++
 bbn_m5atomS3_lite_AS3935_lightning/NmeaXDR.h  | 82 +++++++++++++++++++
 2 files changed, 105 insertions(+)
 create mode 100644 bbn_m5atomS3_lite_AS3935_lightning/NmeaChecksum.h
 create mode 100644 bbn_m5atomS3_lite_AS3935_lightning/NmeaXDR.h

diff --git a/bbn_m5atomS3_lite_AS3935_lightning/NmeaChecksum.h b/bbn_m5atomS3_lite_AS3935_lightning/NmeaChecksum.h
new file mode 100644
index 0000000..6db8331
--- /dev/null
+++ b/bbn_m5atomS3_lite_AS3935_lightning/NmeaChecksum.h
@@ -0,0 +1,23 @@
+#ifndef NmeaChecksum_h
+#define NmeaChecksum_h
+
+#define NMEA_END_CHAR_1    '\r'
+
+/*
+  NMEA-0183 checksum
+ */
+
+uint8_t nmea0183_checksum(const char *sentence);
+
+uint8_t nmea0183_checksum(const char *sentence) {
+  const char *n = sentence + 1;
+  uint8_t chk = 0;
+  /* While current char isn't '*' or sentence ending (newline) */
+  while ('*' != *n && NMEA_END_CHAR_1 != *n && '\0' != *n) {
+    chk ^= (uint8_t) *n;
+    n++;
+  }
+  return chk;
+}
+
+#endif
diff --git a/bbn_m5atomS3_lite_AS3935_lightning/NmeaXDR.h b/bbn_m5atomS3_lite_AS3935_lightning/NmeaXDR.h
new file mode 100644
index 0000000..a835e32
--- /dev/null
+++ b/bbn_m5atomS3_lite_AS3935_lightning/NmeaXDR.h
@@ -0,0 +1,82 @@
+#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,24.57,C,TEMP_BMP280*52
+  $BBXDR,P,101733.00,P,PRES_BMP280*49
+  $BBXDR,H,30.60,P,HUMI_DHT12*60
+  $BBXDR,C,23.40,C,TEMP_DHT12*6D
+  $BBXDR,C,24.58,C,TEMP_BMP280*5D
+  $BBXDR,P,101734.00,P,PRES_BMP280*4E
+  $BBXDR,H,30.30,P,HUMI_DHT12*65
+  $BBXDR,C,23.00,C,TEMP_DHT12*69
+  $BBXDR,C,24.58,C,TEMP_BMP280*5D
+
+
+*/
+
+#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