Fixed problem where newline happens after line is full

Author: davehylands

lcd/lcd_api.py

@@ -56,6 +56,7 @@ def __init__(self, num_lines, num_columns):
             self.num_columns = 40
         self.cursor_x = 0
         self.cursor_y = 0
+        self.implied_newline = False
         self.backlight = True
         self.display_off()
         self.backlight_on()
@@ -135,15 +136,23 @@ def putchar(self, char):
         """Writes the indicated character to the LCD at the current cursor
         position, and advances the cursor by one position.
         """
-        if char != '\n':
+        if char == '\n':
+            if self.implied_newline:
+                # self.implied_newline means we advanced due to a wraparound,
+                # so if we get a newline right after that we ignore it.
+                pass
+            else:
+                self.cursor_x = self.num_columns
+        else:
             self.hal_write_data(ord(char))
             self.cursor_x += 1
-        if self.cursor_x >= self.num_columns or char == '\n':
+        if self.cursor_x >= self.num_columns:
             self.cursor_x = 0
             self.cursor_y += 1
-            if self.cursor_y >= self.num_lines:
-                self.cursor_y = 0
-            self.move_to(self.cursor_x, self.cursor_y)
+            self.implied_newline = (char != '\n')
+        if self.cursor_y >= self.num_lines:
+            self.cursor_y = 0
+        self.move_to(self.cursor_x, self.cursor_y)
 
     def putstr(self, string):
         """Write the indicated string to the LCD at the current cursor