#!/usr/bin/python

# -*- coding: utf-8 -*-

# Python SPI for LPD8806 driven LED strip:

# JGronowski

# First Uploaded: 2015-12-30

# Last Updated: 2016-01-17

#

# Code inspired by:

# ----------------

# github path:

# Adafruit-Raspberry-Pi-Python-Code/Adafruit_LEDpixels/Adafruit_LEDpixels.py

# and the article:

# http://mooresclouddev.markpesce.com/2012/10/18/about-lpd8806-based-rgb-led-strips/

#

# LPD8806 Hardware Examples:

# -----------------

# Digital RGB LED Weatherproof Strip - LPD8806 x 48 LED:

# https://www.adafruit.com/products/1948

# Digital RGB LED Weatherproof Strip - LPD8806 32 LED:

# https://www.adafruit.com/products/306

#

# Usage Notes:

# -----------

# The LPD8806 can be run from a SPI bus using just the SI (data in) and

# SCK (clock) pins. Keep in mind that the LPD8806 cannot share the SPI bus

# with other devices, because of the likelihood of data collisions. True

# SPI devices on the bus will pay attention to the CS (chip select) pin

# signal should not get confused by communication intended for the LED

# strip. The LPD8806 has no device id and will respond to all data on SI.

# The LPD8806 expects three bytes for each LED on the strip--one byte for

# each color component (RGB) of each LED. The first byte corresponds to

# the brightness of the Green light in the first LED. The second byte is Red,

# and the third byte is Blue. The first bit (MSB) of each byte indicates

# whether the subsequent 7 bits should be shifted on to the next LPD8806

# or be held for the current LPD8806. Consiquently, I am using

# 0x00, 0x00, 0x00 to prep the LED strip for new color data. Color data

# ranges from 0x80 0x80 0x80 (all colors off for 1 RGB LED) to

# 0xFF 0xFF 0xFF (all colors full on making 1 RGB LED turn white).

#

# Hardware Setup:

# --------------

# WARNING: Be sure to use logic-level translation on SI (P9_18) and SCK (P9_22),

# because the LPD8806 appears to have an internal pull-up to 5V on both pins!

# The 5 meter LED strip that I got from Adafruit came with double power and

# ground connections (one set is part of the header and one set is loose).

# Connect the extra power and GND pins from the LED strip to a barrel jack.

# https://www.adafruit.com/products/369

# The barrel jack can be used to power the LED strip and the BBB.

# Before plugging the power supply in, use some additional wire to

# connect the strip's terminal to the BBB P9 header pins as above as

# described in the below connection list, and optionally connect the DC5V+ pin

# to the BBB P9_5 pin or P9_6 pin which will supply 5V power to the BBB (these

# are VDD_5V). A 5V 10A power supply from Adafruit is used for the 5 meter strip.

# https://www.adafruit.com/products/658

# A 5V 2A power supply might be good enough for just 1 meter. Be careful

# not to brown out the BBB by turning too many LED's white (all RGB on)

# at the same time if the power supply cannot provide enough current.

#

# BBB pin connections:

# -------------------

# P9_1 (GND) = Power supply GND

# P9_2 (GND) = GND on LPD8806 LED strip

# P9_17 (CS) = N/A (a SPI pin not used by LPD8806)

# P9_18 (SI) = DAT on LDP8806 LED strip (yellow) <-- Remember to use logic-level translation! BBB is 3V, LPD8806 is 5V.

# P9_21 (SO) = N/A (a SPI pin not used by LPD8806)

# P9_22 (SCK) = CLK on the LDP*806 LED strip (green) <-- Remember to use logic-level translation!

#

from Adafruit_BBIO.SPI import SPI

#import Adafruit_BBIO.GPIO as GPIO

import time # useful for wait delay statements

global pixels

class LED_LPD8806(object):

self.writestrip(delay)

#spi.close() # done