Rewrote samples

README.md

@@ -22,7 +22,7 @@ Ideally, a 5$ Raspberry Pi Zero is dedicated to the task of driving the LEDs. Th
 
 ## Wiring
 
-The Raspberry Pi is a 3.3 Volt device, and the APA102 LEDs are 5 Volt devices. Therefore it's possible that the 3.3 Volt SPI signal is not being recognized by the LED driver chips. To avoid this risk, use a 74AHCT125 level shifter for both the clock and the MOSI signal.
+The Raspberry Pi is a 3.3 Volt device, and the APA102 LEDs are 5 Volt devices. Therefore it's possible that the 3.3 Volt SPI signal is not being recognized by the LED driver chips. To avoid this risk, use a 74AHCT125 or 74AHC125 level shifter for both the clock and the MOSI signal.
 
 Without a level shifter, the wiring is very simple:
 - LED ground to one of the Raspberry ground pins
@@ -49,4 +49,9 @@ Videos can't be embedded yet, so head over to youtube: https://youtu.be/N0MK1z8W
 
 
 ## Using the library
-TODO
+TODO
+
+## Release history
+2015-04-13: Initial version
+2015-12-04: Add documentation
+2015-12-11: Rewrote the examples, driver itself is unchanged

basecolorcycle.py

@@ -0,0 +1,56 @@
+import apa102
+import time
+
+"""
+This class is the basis of all color cycles, such as rainbow or theater chase.
+"""
+
+class BaseColorCycle:
+    def __init__(self, numLEDs, pauseValue = 0, globalBrightness = 31): # Init method
+        self.numLEDs = numLEDs
+        self.pauseValuse = pauseValue
+        self.globalBrightness = globalBrightness
+        timeOfLastCall = 0
+        cycleCounter = 0
+
+    """
+    void init()
+    This method is called to initialize a color program.
+    """
+    def init(self):
+    	  # The default does nothing. A particular subclass could e.g. light all LEDs to white.
+    	  print('Init')
+
+    """
+    void shutdown()
+    This method is called at the end, when the light program shoule terminate
+    """
+    def shutdown(self):
+        # The default does nothing
+        print('Shutdown')
+
+    """
+    void update()
+    This method paints one cycle. It must be implemented
+    """
+    def update(self):
+    	  raise NotImplementedError("Please implement the update() method")
+
+    """
+    Start the actual work
+    """
+
+    try:
+        strip = apa102.APA102(numPixels, globalBrightness) # Low brightness (2 out of max. 31)
+        while True:  # Loop forever
+            cycleCounter += 1
+            update()
+            strip.show()
+            time.sleep(pauseValue)
+
+    except KeyboardInterrupt:  # Abbruch...
+        print('Interrupted...')
+        strip.clearStrip()
+        print('Strip cleared')
+        strip.cleanup()
+        print('SPI closed')

colorcycletemplate.py

@@ -0,0 +1,75 @@
+import apa102
+import time
+
+"""
+This class is the basis of all color cycles, such as rainbow or theater chase.
+A specific color cycle must subclass this template, and implement at least the
+'update' method.
+"""
+class ColorCycleTemplate:
+    def __init__(self, numLEDs, pauseValue = 0, numCycles = -1, globalBrightness = 4): # Init method
+        self.numLEDs = numLEDs # The number of LEDs in the strip
+        self.pauseValue = pauseValue # How long to pause between two runs
+        self.numCycles = numCycles # How many times will the program run
+        self.globalBrightness = globalBrightness # Brightness of the strip
+
+    """
+    void init()
+    This method is called to initialize a color program.
+    """
+    def init(self, strip, numLEDs):
+    	  # The default does nothing. A particular subclass could setup variables, or
+    	  # even light the strip in an initial color.
+    	  print('Init not implemented')
+
+    """
+    void shutdown()
+    This method is called at the end, when the light program should terminate
+    """
+    def shutdown(self, strip, numLEDs):
+        # The default does nothing
+        print('Shutdown not implemented')
+
+    """
+    void update()
+    This method paints one subcycle. It must be implemented
+    currentStep: This goes from zero to numLEDs, and then back to zero
+    currentCycle: Counts up whenever the currentStep goes back to zero
+    """
+    def update(self, strip, numLEDs, currentStep, currentCycle):
+    	  raise NotImplementedError("Please implement the update() method")
+
+    def cleanup(self, strip):
+        self.shutdown(strip, self.numLEDs)
+        strip.clearStrip()
+        print('Strip cleared')
+        strip.cleanup()
+        print('SPI closed')
+
+    """
+    Start the actual work
+    """
+    def start(self):
+        try:
+            strip = apa102.APA102(self.numLEDs, self.globalBrightness) # Initialize the strip
+            strip.clearStrip()
+            self.init(strip, self.numLEDs) # Call the subclasses init method
+            strip.show()
+            currentCycle = 0
+            currentStep = 0
+            while True:  # Loop forever
+                needRepaint = self.update(strip, self.numLEDs, currentStep, currentCycle) # Call the subclasses update method
+                if (needRepaint): strip.show() # Display, only if required
+                time.sleep(self.pauseValue) # Pause until the next iteration
+                currentStep += 1
+                if (currentStep >= self.numLEDs):
+                    currentStep = 0 # Start next loop
+                    currentCycle += 1
+                    if (self.numCycles != -1):
+                        if (currentCycle >= self.numCycles): break
+            # Finished, cleanup everything
+            self.cleanup(strip)
+
+        except KeyboardInterrupt:  # Ctrl-C can halt the light program
+            print('Interrupted...')
+            self.cleanup(strip)

colorschemes.py

@@ -0,0 +1,50 @@
+from colorcycletemplate import ColorCycleTemplate
+
+class StrandTest(ColorCycleTemplate):
+
+    def init(self, strip, numLEDs):
+        self.color = 0x000000  # Initialize with black
+
+    def update(self, strip, numLEDs, currentStep, currentCycle):
+        if (currentStep == 0): self.color >>= 8  # Red->green->blue->black
+        if (self.color == 0): self.color = 0xFF0000  # If black, reset to red
+
+        head = (currentStep + 9) % numLEDs # The head pixel that will be turned on in this cycle
+        tail = currentStep # The tail pixel that will be turned off
+        strip.setPixelRGB(head, self.color)  # Paint head
+        strip.setPixelRGB(tail, 0)  # Clear tail
+
+        return 1 # Repaint is necessary
+
+
+class TheaterChase(ColorCycleTemplate):
+    def update(self, strip, numLEDs, currentStep, currentCycle):
+        startIndex = currentStep % 7 # Each segment is 7 dots long: 2 blank, and 5 filled
+        colorIndex = strip.wheel((currentCycle*numLEDs+currentStep) % 255)
+        for pixel in range(numLEDs):
+        	  # Two LEDs out of 7 are blank. At each step, the blank ones move one pixel ahead.
+            if ((pixel+startIndex) % 7 == 0) or ((pixel+startIndex) % 7 == 1): strip.setPixelRGB(pixel, 0)
+            else: strip.setPixelRGB(pixel, colorIndex)
+        return 1
+
+
+
+class Solid(ColorCycleTemplate):
+
+    def init(self, strip, numLEDs):
+    	  for led in range(0, numLEDs):
+    	  	  strip.setPixelRGB(led,0xFFFFFF) # Paint white
+
+    def update(self, strip, numLEDs, currentStep, currentCycle):
+    	  # Do nothing: Init lit the strip, and update just keeps it this way
+    	  return 0
+
+
+class Rainbow(ColorCycleTemplate):
+    def update(self, strip, numLEDs, currentStep, currentCycle):
+        shiftCounter = currentCycle * numLEDs + currentStep
+        for i in range(numLEDs): # spread (or compress) one rainbow onto the strip
+            # For a faster shift, add more than 1 * j per loop (e.g. + 2 * j)
+            index = strip.wheel((((i << 8) // numLEDs) + shiftCounter) & 255)
+            strip.setPixelRGB(i, index);
+        return 1 # Repaint the strip

runColorCycle.py

@@ -0,0 +1,10 @@
+import colorschemes
+
+myCycle = colorschemes.Solid(numLEDs=430, pauseValue=0.01, numCycles = 1)
+myCycle.start()
+myCycle = colorschemes.StrandTest(numLEDs=430, pauseValue=0, numCycles = 4, globalBrightness=10)
+myCycle.start()
+myCycle = colorschemes.Rainbow(numLEDs=430, pauseValue=0, numCycles = 6, globalBrightness=10)
+myCycle.start()
+myCycle = colorschemes.TheaterChase(numLEDs=430, pauseValue=0.04, numCycles = 2, globalBrightness=10)
+myCycle.start()