Files
lamatrix/ws2812.py
Noah 3e4dd4c0bc Rewrite to reduce memory usage and add more features
In addition to the clock scene, both the animation scene and the weather
scene should now work under MicroPython on devices with 520kBytes of RAM
(e.g. LoPy 1, WiPy 2) after:

- combating heap fragmentation during initialization by temporarily allocating
  a large chunk of RAM in the beginning of main.py and freeing it after all
  modules have been imported and initialized
- stream parsing the JSON response from the weather API
- converting animations to binary and streaming them from the flash file system

(additionally, older ESP8266 modules with 4MB flash have been found working
 under some circumstances with MicroPython 1.9.4 and an 8x8 LED matrix)

- 3D parts: add diffuser grid and frame for square LED matrix displays
- Arduino projects needs to be in a folder with the same name as the .ino file
- config: allow multiple WiFi networks to be configured
- config: add support for debug flags
- config: add intensity configuration
- HAL: unify serial input processing for Arduino and Pycom devices
- HAL: handle UART write failures on Pycom devices
- HAL: drop garbage collection from .update_display() because it takes several
  hundred milliseconds on 4MB devices
- MCU: clear display when enabling/disabling MCU independence from host
- PixelFont: move data to class attributes to reduce memory usage
- PixelFont: add more characters
- PixelFont: move data generation to scripts/generate-pixelfont.py
- LedMatrix: support LED matrixes with strides other than 8 (e.g. as 16x16 matrices)
- LedMatrix: add method to render text
- LedMatrix: let consumers handle brightness themselves
- AnimationScene: MicroPython does not implement bytearray.find
- AnimationScene: ensure minimum on-screen time
- BootScene: wifi connection and RTC sync progress for Pycom devices
- ClockScene: delete unused code, switch to generic text rendering method
- FireScene: classical fire effect
- WeatherScene: bug fixes, switch to generic text rendering method
- WeatherScene: ensure minimum on-screen time
- WeatherScene: use custom JSON parsing to reduce memory usage
2018-12-26 20:26:05 +00:00

95 lines
2.6 KiB
Python

# -*- coding: utf-8 -*-
"""This code is borrowed from https://github.com/JanBednarik/micropython-ws2812
It has been modified to work on, and has been tested upon, the Pycom WiPy 2.0 board.
It uses SPI MOSI (Master-out Slave-in) which is P11 or (on the pymakr board) G22.
See: https://docs.pycom.io/chapter/datasheets/downloads/wipy2-pinout.pdf
Modifications include:
* Changing buf_bytes to 0b representation for clearer view of what's happening internally
* Switch to machine.SPI instead of pyb.SPIfor Pycom WiPy 2.0 board
* Adding disable_irq and enable_irq to prevent interrupts firing mid-transaction and causing a premature reset
"""
import gc
from machine import SPI
from machine import disable_irq
from machine import enable_irq
class WS2812:
"""
Driver for WS2812 RGB LEDs. May be used for controlling single LED or chain
of LEDs.
Example of use:
chain = WS2812(spi_bus=1, led_count=4)
data = [
(255, 0, 0), # red
(0, 255, 0), # green
(0, 0, 255), # blue
(85, 85, 85), # white
]
chain.show(data)
Version: 1.0
"""
buf_bytes = (0b000010001, 0b00010011, 0b00110001, 0b00110011)
def __init__(self, spi_bus=0, ledNumber=1, intensity=1):
"""
Params:
* spi_bus = SPI bus ID (1 or 2)
* led_count = count of LEDs
* intensity = light intensity (float up to 1)
"""
self.led_count = ledNumber
self.intensity = intensity
# prepare SPI data buffer (4 bytes for each color)
self.buf_length = self.led_count * 3 * 4
self.buf = bytearray(self.buf_length)
# SPI init
self.spi = SPI(spi_bus, SPI.MASTER, baudrate=3200000, polarity=0, phase=1)
# turn LEDs off
self.send_buf()
def send_buf(self):
"""
Send buffer over SPI.
"""
disable_irq()
self.spi.write(self.buf)
enable_irq()
# NOTE: show(), update_buf() and fill_buf() were replaced
# with these to reduce memory usage in pycomhal.py
def clear(self):
# turn off the rest of the LEDs
buf = self.buf
off = self.buf_bytes[0]
for index in range(self.buf_length):
buf[index] = off
index += 1
def put_pixel(self, addr, red, green, blue):
buf = self.buf
buf_bytes = self.buf_bytes
mask = 0x03
index = addr * 12
buf[index] = buf_bytes[green >> 6 & mask]
buf[index+1] = buf_bytes[green >> 4 & mask]
buf[index+2] = buf_bytes[green >> 2 & mask]
buf[index+3] = buf_bytes[green & mask]
buf[index+4] = buf_bytes[red >> 6 & mask]
buf[index+5] = buf_bytes[red >> 4 & mask]
buf[index+6] = buf_bytes[red >> 2 & mask]
buf[index+7] = buf_bytes[red & mask]
buf[index+8] = buf_bytes[blue >> 6 & mask]
buf[index+9] = buf_bytes[blue >> 4 & mask]
buf[index+10] = buf_bytes[blue >> 2 & mask]
buf[index+11] = buf_bytes[blue & mask]