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wasp-os/wasp/drivers/st7789.py
Daniel Thompson fd64abe882 wasp: draw565: Optimize the 2-bit RLE drawing functions
There's a bunch of different changes here but there are only really three
big wins. The biggest win comes from restructuring the 2-bit RLE decode
loop to avoid the inner function (~20%) but the switch to 16-bit writes in
_fill() and adoption of quick_write (e.g. no CS toggling) are also
note worthy (and about 5% each).
2020-04-08 21:50:42 +01:00

167 lines
4.3 KiB
Python

# SPDX-License-Identifier: LGPL-3.0-or-later
# Copyright (C) 2020 Daniel Thompson
"""Sitronix ST7789 display driver for MicroPython.
Note: Although the ST7789 supports a variety of communication protocols
currently this driver only has support for SPI interfaces. However it is
structured such that other serial protocols can easily be added.
"""
import micropython
from micropython import const
from time import sleep_ms
# register definitions
_SWRESET = const(0x01)
_SLPIN = const(0x10)
_SLPOUT = const(0x11)
_NORON = const(0x13)
_INVOFF = const(0x20)
_INVON = const(0x21)
_DISPOFF = const(0x28)
_DISPON = const(0x29)
_CASET = const(0x2a)
_RASET = const(0x2b)
_RAMWR = const(0x2c)
_COLMOD = const(0x3a)
_MADCTL = const(0x36)
class ST7789(object):
def __init__(self, width, height):
self.width = width
self.height = height
self.linebuffer = bytearray(2 * width)
self.init_display()
def init_display(self):
self.reset()
self.write_cmd(_SLPOUT)
sleep_ms(10)
for cmd in (
(_COLMOD, b'\x05'), # MCU will send 16-bit RGB565
(_MADCTL, b'\x00'), # Left to right, top to bottom
#(_INVOFF, None), # Results in odd palette
(_INVON, None),
(_NORON, None),
):
self.write_cmd(cmd[0])
if cmd[1]:
self.write_data(cmd[1])
self.fill(0)
self.write_cmd(_DISPON)
# From the point we sent the SLPOUT there must be a
# 120ms gap before any subsequent SLPIN. In most cases
# (i.e. wen the SPI baud rate is slower than 8M then
# that time already elapsed as we zeroed the RAM).
#sleep_ms(125)
def poweroff(self):
self.write_cmd(_SLPIN)
sleep_ms(125)
def poweron(self):
self.write_cmd(_SLPOUT)
sleep_ms(125)
def contrast(self, contrast):
pass
def invert(self, invert):
if invert:
self.write_cmd(_INVON)
else:
self.write_cmd(_INVOFF)
def mute(self, mute):
if mute:
self.write_cmd(_DISPOFF)
else:
self.write_cmd(_DISPON)
def set_window(self, x=0, y=0, width=None, height=None):
if not width:
width = self.width
if not height:
height = self.height
xp = x + width - 1
yp = y + height - 1
self.write_cmd(_CASET)
self.write_data(bytearray([x >> 8, x & 0xff, xp >> 8, xp & 0xff]))
self.write_cmd(_RASET)
self.write_data(bytearray([y >> 8, y & 0xff, yp >> 8, yp & 0xff]))
self.write_cmd(_RAMWR)
def rawblit(self, buf, x, y, width, height):
self.set_window(x, y, width, height)
self.write_data(buf)
def fill(self, bg, x=0, y=0, w=None, h=None):
if not w:
w = self.width - x
if not h:
h = self.height - y
self.set_window(x, y, w, h)
# Populate the line buffer
buf = memoryview(self.linebuffer)[0:2*w]
for xi in range(0, 2*w, 2):
buf[xi] = bg >> 8
buf[xi+1] = bg & 0xff
# Do the fill
for yi in range(h):
self.write_data(buf)
class ST7789_SPI(ST7789):
def __init__(self, width, height, spi, cs, dc, res=None, rate=8000000):
self.quick_write = spi.write
self.cs = cs.value
self.dc = dc.value
self.res = res
self.rate = rate
#spi.init(baudrate=self.rate, polarity=1, phase=1)
cs.init(cs.OUT, value=1)
dc.init(dc.OUT, value=0)
if res:
res.init(res.OUT, value=0)
super().__init__(width, height)
def reset(self):
if self.res:
self.res(0)
sleep_ms(10)
self.res(1)
else:
self.write_cmd(_SWRESET)
sleep_ms(125)
def write_cmd(self, cmd):
dc = self.dc
cs = self.cs
dc(0)
cs(0)
self.quick_write(bytearray([cmd]))
cs(1)
dc(1)
def write_data(self, buf):
cs = self.cs
cs(0)
self.quick_write(buf)
cs(1)
def quick_start(self):
self.cs(0)
def quick_end(self):
self.cs(1)