X-Git-Url: https://git.ayoreis.com/hackapet/Adafruit_Blinka.git/blobdiff_plain/3f017a27633d001cdb30d6e36bfce3baea3ab52d..40b64d58a1a537ccc55e1c45fe6804b495c6e055:/src/adafruit_blinka/microcontroller/bcm283x/neopixel.py

diff --git a/src/adafruit_blinka/microcontroller/bcm283x/neopixel.py b/src/adafruit_blinka/microcontroller/bcm283x/neopixel.py
new file mode 100644
index 0000000..d744b25
--- /dev/null
+++ b/src/adafruit_blinka/microcontroller/bcm283x/neopixel.py
@@ -0,0 +1,104 @@
+import time
+import math
+import _rpi_ws281x as ws
+import atexit
+
+# LED configuration.
+LED_CHANNEL    = 0
+LED_FREQ_HZ    = 800000     # Frequency of the LED signal.  We only support 800KHz
+LED_DMA_NUM    = 10         # DMA channel to use, can be 0-14.
+LED_BRIGHTNESS = 255        # We manage the brightness in the neopixel library
+LED_INVERT     = 0          # We don't support inverted logic
+LED_STRIP      = None # We manage the color order within the neopixel library
+
+# a 'static' object that we will use to manage our PWM DMA channel
+# we only support one LED strip per raspi
+_led_strip = None
+
+def neopixel_write(gpio, buf):
+    global _led_strip # we'll have one strip we init if its not at first
+
+    if _led_strip is None:
+        # Create a ws2811_t structure from the LED configuration.
+        # Note that this structure will be created on the heap so you
+        # need to be careful that you delete its memory by calling
+        # delete_ws2811_t when it's not needed.
+        _led_strip = ws.new_ws2811_t()
+
+        # Initialize all channels to off
+        for channum in range(2):
+            channel = ws.ws2811_channel_get(_led_strip, channum)
+            ws.ws2811_channel_t_count_set(channel, 0)
+            ws.ws2811_channel_t_gpionum_set(channel, 0)
+            ws.ws2811_channel_t_invert_set(channel, 0)
+            ws.ws2811_channel_t_brightness_set(channel, 0)
+
+        channel = ws.ws2811_channel_get(_led_strip, LED_CHANNEL)
+
+        # Initialize the channel in use
+        count = 0
+        if len(buf) % 3 == 0:
+            # most common, divisible by 3 is likely RGB
+            LED_STRIP = ws.WS2811_STRIP_RGB
+            count = len(buf)//3
+        elif len(buf) % 4 == 0:
+            LED_STRIP = ws.SK6812_STRIP_RGBW
+            count = len(buf)//4
+        else:
+            raise RuntimeError("We only support 3 or 4 bytes-per-pixel")
+
+        ws.ws2811_channel_t_count_set(channel, count) # we manage 4 vs 3 bytes in the library
+        ws.ws2811_channel_t_gpionum_set(channel, gpio._pin.id)
+        ws.ws2811_channel_t_invert_set(channel, LED_INVERT)
+        ws.ws2811_channel_t_brightness_set(channel, LED_BRIGHTNESS)
+        ws.ws2811_channel_t_strip_type_set(channel, LED_STRIP)
+
+        # Initialize the controller
+        ws.ws2811_t_freq_set(_led_strip, LED_FREQ_HZ)
+        ws.ws2811_t_dmanum_set(_led_strip, LED_DMA_NUM)
+
+        resp = ws.ws2811_init(_led_strip)
+        if resp != ws.WS2811_SUCCESS:
+            if resp == -5:
+                raise RuntimeError("NeoPixel support requires running with sudo, please try again!")
+            message = ws.ws2811_get_return_t_str(resp)
+            raise RuntimeError('ws2811_init failed with code {0} ({1})'.format(resp, message))
+        atexit.register(neopixel_cleanup)
+
+    channel = ws.ws2811_channel_get(_led_strip, LED_CHANNEL)
+    if gpio._pin.id != ws.ws2811_channel_t_gpionum_get(channel):
+        raise RuntimeError("Raspberry Pi neopixel support is for one strip only!")
+
+    if ws.ws2811_channel_t_strip_type_get(channel) == ws.WS2811_STRIP_RGB:
+        bpp = 3
+    else:
+        bpp = 4
+    # assign all colors!
+    for i in range(len(buf) // bpp):
+        r = buf[bpp*i]
+        g = buf[bpp*i+1]
+        b = buf[bpp*i+2]
+        if bpp == 3:
+            pixel = (r << 16) | (g << 8) | b
+        else:
+            w = buf[bpp*i+3]
+            pixel = (w << 24) | (r << 16) | (g << 8) | b
+        ws.ws2811_led_set(channel, i, pixel)
+
+    resp = ws.ws2811_render(_led_strip)
+    if resp != ws.WS2811_SUCCESS:
+        message = ws.ws2811_get_return_t_str(resp)
+        raise RuntimeError('ws2811_render failed with code {0} ({1})'.format(resp, message))
+    time.sleep(0.001 * ((len(buf)//100)+1))  # about 1ms per 100 bytes
+
+
+def neopixel_cleanup():
+    global _led_strip
+
+    if _led_strip is not None:
+        # Ensure ws2811_fini is called before the program quits.
+        ws.ws2811_fini(_led_strip)
+        # Example of calling delete function to clean up structure memory.  Isn't
+        # strictly necessary at the end of the program execution here, but is good practice.
+        ws.delete_ws2811_t(_led_strip)
+        _led_strip = None