From 968e95344c82b84ce529d8ee53212fb3b411d8f0 Mon Sep 17 00:00:00 2001
From: Rick Sellens <sellensr@queensu.ca>
Date: Tue, 16 Apr 2019 12:49:05 -0400
Subject: [PATCH] Revert "parse checksum to *"

This reverts commit 0f867b508a8d5c4ac89c3a902275b8407c76d39a.
---
 Adafruit_GPS.cpp | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/Adafruit_GPS.cpp b/Adafruit_GPS.cpp
index 0535d57..20a167b 100755
--- a/Adafruit_GPS.cpp
+++ b/Adafruit_GPS.cpp
@@ -55,14 +55,13 @@ boolean Adafruit_GPS::parse(char *nmea) {
   // do checksum check
 
   // first look if we even have one
-  char *ast = strchr(nmea,'*');
-  if (ast != NULL) {
-    uint16_t sum = parseHex(*(ast+1)) * 16;
-    sum += parseHex(*(ast+2));
+  if (nmea[strlen(nmea)-4] == '*') {
+    uint16_t sum = parseHex(nmea[strlen(nmea)-3]) * 16;
+    sum += parseHex(nmea[strlen(nmea)-2]);
 
     // check checksum
-    for (char *p = nmea+2; p < ast; p++) {
-      sum ^= *p;
+    for (uint8_t i=2; i < (strlen(nmea)-4); i++) {
+      sum ^= nmea[i];
     }
     if (sum != 0) {
       // bad checksum :(