added lcd example

the way text is generated is currently rather awkward, looking for a
better solution.

examples/efm32/tinygecko/efm32-tg-stk3300/lcd_demo/generate_lcd_mapping.py

@@ -0,0 +1,76 @@
+#!/usr/bin/env python
+
+import yaml
+
+class Font(dict):
+    def __init__(self, letterdict):
+        for (k, v) in letterdict.items():
+            self[k] = set(v.split())
+
+class Display(object):
+    def __init__(self, data):
+        self.mapping = {}
+
+        for c, segs in enumerate(data['coms']):
+            for s, name in enumerate(segs):
+                self.mapping[name] = (c, s)
+
+    def render_text(self, text, symbols, font):
+        cursor = 1
+        segments = set()
+        for letter in text:
+            if letter == '.':
+                segments.add("a%s_dp"%(cursor-1))
+            elif letter == ':':
+                segments.add("a%s_colon"%(cursor-1))
+            elif letter in font:
+                for segment in font[letter]:
+                    segments.add("a%s_%s"%(cursor, segment))
+                cursor += 1
+
+        for s in symbols:
+            segments.add(s)
+
+        coms = {}
+        for segment in segments:
+            com, seg = self.mapping[segment]
+            coms[com] = coms.get(com, 0) | (1<<seg)
+
+        return coms
+
+def main():
+    data = yaml.load(open("lcd_mapping.yaml"))
+
+    d = Display(data)
+
+    text = "{FNORD}"
+    symbols = ['gecko']
+    f = Font({
+        '-': 'g1 g2',
+        'A': 'e f a b c g1 g2',
+        'C': 'a f e d',
+        'D': 'a b c d i l',
+        'E': 'a f g1 g2 e d',
+        'F': 'a f g1 g2 e',
+        'H': "f b g1 g2 e c",
+        'I': "i l a d",
+        'L': 'f e d',
+        'M': 'e f h j b c',
+        'N': 'e f h m c b',
+        'O': 'a f e d c b',
+        'R': 'a e f g1 j m',
+        'T': 'i l a',
+        'U': 'f e d c b',
+        '[': 'a d e f',
+        ']': 'a b c d',
+        '{': 'a d k h g1',
+        '}': 'a j g2 m d',
+        })
+
+    for com, data in d.render_text(text, symbols, f).items():
+        print "set_bank(%d, %#08.0x);"%(com, data)
+#    with open('lcd_mapping.c', 'w') as outfile:
+#        for symbol in data['symbols']:
+
+if __name__ == "__main__":
+    main()