LED 8x8 example

python/samples/ht16k33.py

@@ -0,0 +1,22 @@
+class HT16K33:
+    def __init__(self, i2, a = 0x70):
+        self.i2 = i2
+        self.a = a
+        self.command(0x21)      # Clock on
+        self.command(0x81)      # Display on
+        self.bright(15)
+        self.load([0] * 16)
+
+    def bright(self, n):
+        assert 0 <= n < 16
+        self.command(0xe0 + n)
+
+    def command(self, b):
+        assert(self.i2.start(self.a, 0))
+        assert(self.i2.write([b]))
+        self.i2.stop()
+
+    def load(self, b128):
+        self.i2.start(self.a, 0)
+        self.i2.write([0] + b128)
+        self.i2.stop()

python/samples/led8x8.py

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+"""
+Example for 8x8 LED Matrix modules, based on HT16K33.
+Available from multiple vendors.
+"""
+
+import sys
+import time
+
+from i2cdriver import I2CDriver
+
+font = open("cp437-8x8", "rb").read()
+
+from ht16k33 import HT16K33
+
+class led8x8(HT16K33):
+    def image(self, bb):
+        """ Set the pixels to the bytes bb """
+        def swiz(b):
+            bs = [str((b >> n) & 1) for n in range(8)]
+            return int(bs[7] + bs[0] + bs[1] + bs[2] + bs[3] + bs[4] + bs[5] + bs[6], 2)
+        bb = [swiz(b) for b in bb]
+        self.load([b for s in zip(bb,bb) for b in s])
+
+    def char(self, c):
+        """ Set the pixels to character c """
+        n = ord(c)
+        ch = font[n * 8:n * 8 + 8]
+        self.image(ch)
+
+if __name__ == '__main__':
+    i2 = I2CDriver(sys.argv[1])
+
+    d = led8x8(i2)
+
+    for c in "I2C":
+        d.char(c)
+        time.sleep(1)