From 240f1bbdea4754bd6d8322b9e3b8aa7a6b41af58 Mon Sep 17 00:00:00 2001
From: Tony DiCola <tony@tonydicola.com>
Date: Mon, 11 Aug 2014 11:01:50 -0700
Subject: [PATCH] Add fixed point minute scaling back with correct floating
 point conversion.

---
 Adafruit_GPS.cpp | 16 ++++++++--------
 Adafruit_GPS.h   |  6 +++---
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/Adafruit_GPS.cpp b/Adafruit_GPS.cpp
index d5c3205..fd5503d 100755
--- a/Adafruit_GPS.cpp
+++ b/Adafruit_GPS.cpp
@@ -72,9 +72,9 @@ boolean Adafruit_GPS::parse(char *nmea) {
     p += 3; // skip decimal point
     strncpy(degreebuff + 2, p, 4);
     degreebuff[6] = '\0';
-    long minutes = atol(degreebuff) * 10;
+    long minutes = 50 * atol(degreebuff) / 3;
     latitude_fixed = degree + minutes;
-    latitude = latitude_fixed / 100000.0F;
+    latitude = degree / 100000 + minutes * 0.000006F;
 
     p = strchr(p, ',')+1;
     if (p[0] == 'N') lat = 'N';
@@ -92,9 +92,9 @@ boolean Adafruit_GPS::parse(char *nmea) {
     p += 3; // skip decimal point
     strncpy(degreebuff + 2, p, 4);
     degreebuff[6] = '\0';
-    minutes = atol(degreebuff) * 10;
+    minutes = 50 * atol(degreebuff) / 3;
     longitude_fixed = degree + minutes;
-    longitude = longitude_fixed / 100000.0F;
+    longitude = degree / 100000 + minutes * 0.000006F;
 
     p = strchr(p, ',')+1;
     if (p[0] == 'W') lon = 'W';
@@ -151,9 +151,9 @@ boolean Adafruit_GPS::parse(char *nmea) {
     p += 3; // skip decimal point
     strncpy(degreebuff + 2, p, 4);
     degreebuff[6] = '\0';
-    long minutes = atol(degreebuff) * 10;
+    long minutes = 50 * atol(degreebuff) / 3;
     latitude_fixed = degree + minutes;
-    latitude = latitude_fixed / 100000.0F;
+    latitude = degree / 100000 + minutes * 0.000006F;
 
     p = strchr(p, ',')+1;
     if (p[0] == 'N') lat = 'N';
@@ -171,9 +171,9 @@ boolean Adafruit_GPS::parse(char *nmea) {
     p += 3; // skip decimal point
     strncpy(degreebuff + 2, p, 4);
     degreebuff[6] = '\0';
-    minutes = atol(degreebuff) * 10;
+    minutes = 50 * atol(degreebuff) / 3;
     longitude_fixed = degree + minutes;
-    longitude = longitude_fixed / 100000.0F;
+    longitude = degree / 100000 + minutes * 0.000006F;
 
     p = strchr(p, ',')+1;
     if (p[0] == 'W') lon = 'W';
diff --git a/Adafruit_GPS.h b/Adafruit_GPS.h
index 375cc6d..1cdad58 100755
--- a/Adafruit_GPS.h
+++ b/Adafruit_GPS.h
@@ -127,9 +127,9 @@ class Adafruit_GPS {
   uint16_t milliseconds;
   // Floating point latitude and longitude value in degrees.
   float latitude, longitude;
-  // Fixed point latitude and longitude value in 1/100000 degrees.
-  // For example a latitude of 4,767.99916 degrees would have a value of 476799916.
-  // More precise than the floating point value, but a little more difficult to use.
+  // Fixed point latitude and longitude value with degrees stored in units of 1/100000 degrees,
+  // and minutes stored in units of 1/100000 degrees.  See pull #13 for more details:
+  //   https://github.com/adafruit/Adafruit-GPS-Library/pull/13
   int32_t latitude_fixed, longitude_fixed;
   float geoidheight, altitude;
   float speed, angle, magvariation, HDOP;