第3回の記事
ラズパイ5 2023年10月更新 bookworm ③ pipが使えない！ pythonでグラフィック・ディスプレイを利用
では、グラフィック・ディスプレイAdafruit 2.0" 320x240 Color IPS TFT Displayを、仮想環境で使うことができませんでした。
ここでは、力ずくで、動かします。
仮想環境に入る
envtftという仮想環境を作り、入ります。
yoshi@ras05:~ $ python -m venv envtft
yoshi@ras05:~ $ source envtft/bin/activate
(envtft) yoshi@ras05:~ $
ライブラリ（モジュール）は空っぽです。
(envtft) yoshi@ras05:~ $ pip list
Package Version
---------- -------
pip 23.0.1
setuptools 66.1.1
この仮想環境で、st7789ライブラリをpipを使ってインストールします。
st7789ライブラリのインストール
(envtft) yoshi@ras05:~ $ pip install st7789
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Collecting st7789
Using cached https://www.piwheels.org/simple/st7789/ST7789-0.0.4-py3-none-any.whl (8.4 kB)
Installing collected packages: st7789
Successfully installed st7789-0.0.4
envtft) yoshi@ras05:~ $ pip list
Package Version
---------- -------
pip 23.0.1
setuptools 66.1.1
ST7789 0.0.4
実行に必要な、pillow、numpy、spidev、RPi.GPIOをインストールします。
(envtft) yoshi@ras05:~ $ pip list
Package Version
---------- -------
numpy 1.26.4
pillow 10.2.0
pip 23.0.1
RPi.GPIO 0.7.1
setuptools 66.1.1
spidev 3.6
ST7789 0.0.4
次の表示プログラムst7789a.pyを動かします。
from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont
import ST7789
MESSAGE = "Hello World!"
print(MESSAGE)
#display_type == "dhmini":
disp = ST7789.ST7789(
height=240,
width=320,
rotation=0,
port=0,
cs=0,
dc=22,
rst=25,
backlight=None,
spi_speed_hz=80 * 1000 * 1000,
)
# Initialize display.
disp.begin()
WIDTH = disp.width
HEIGHT = disp.height
img = Image.new('RGB', (WIDTH, HEIGHT), color=(255, 0, 0))
draw = ImageDraw.Draw(img)
font = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf", 30)
draw.text((20,20),MESSAGE, font=font, fill=(255,255,255))
disp.display(img)
エラーが出ます。
(envtft) yoshi@ras05:~ $ python st7789a.py
Hello World!
Traceback (most recent call last):
File "/home/yoshi/st7789a.py", line 11, in <module>
disp = ST7789.ST7789(
^^^^^^^^^^^^^^
File "/home/yoshi/envtft/lib/python3.11/site-packages/ST7789/__init__.py", line 139, in __init__
GPIO.setup(dc, GPIO.OUT)
RuntimeError: Cannot determine SOC peripheral base address
このエラーは、ラズパイ5ではGPIOをアクセスするライブラリのRPi.GPIOが対応していないためです。ラズパイでは、gapiozeroライブラリをつかうべしという話が見つかります。そこで、/home/yoshi/envtft/lib/python3.11/site-packages/ST7789/__init__.pyのRPi.GPIOを利用しているところを、gapiozeroライブラリのコマンドで置き換えました。
実行すると、二つのエラーが出ました。一つは、rpi-lgpioをインストールすると消えましたが、もう一つ残っています。
GPIOの操作は、rst（リセット信号）、dc信号をON/OFFしているだけです。なので、subprocess.run(）で、export /sys。。。/gpio1のようなGPIOを直にON/OFFしようと書き替えました。しかし、このexport操作は、ラズパイ5では使えなくなっていることがわかりました。
使えるのはpinctrlですね。新しいshellで使えるコマンドです。GPIOの操作は、このコマンドに書き換えました。
__init__.py
# Copyright (c) 2014 Adafruit Industries
# Author: Tony DiCola
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
import numbers
import time
import numpy as np
import spidev
# import RPi.GPIO as GPIO
import subprocess
__version__ = '0.0.4'
BG_SPI_CS_BACK = 0
BG_SPI_CS_FRONT = 1
SPI_CLOCK_HZ = 16000000
ST7789_NOP = 0x00
ST7789_SWRESET = 0x01
ST7789_RDDID = 0x04
ST7789_RDDST = 0x09
ST7789_SLPIN = 0x10
ST7789_SLPOUT = 0x11
ST7789_PTLON = 0x12
ST7789_NORON = 0x13
ST7789_INVOFF = 0x20
ST7789_INVON = 0x21
ST7789_DISPOFF = 0x28
ST7789_DISPON = 0x29
ST7789_CASET = 0x2A
ST7789_RASET = 0x2B
ST7789_RAMWR = 0x2C
ST7789_RAMRD = 0x2E
ST7789_PTLAR = 0x30
ST7789_MADCTL = 0x36
ST7789_COLMOD = 0x3A
ST7789_FRMCTR1 = 0xB1
ST7789_FRMCTR2 = 0xB2
ST7789_FRMCTR3 = 0xB3
ST7789_INVCTR = 0xB4
ST7789_DISSET5 = 0xB6
ST7789_GCTRL = 0xB7
ST7789_GTADJ = 0xB8
ST7789_VCOMS = 0xBB
ST7789_LCMCTRL = 0xC0
ST7789_IDSET = 0xC1
ST7789_VDVVRHEN = 0xC2
ST7789_VRHS = 0xC3
ST7789_VDVS = 0xC4
ST7789_VMCTR1 = 0xC5
ST7789_FRCTRL2 = 0xC6
ST7789_CABCCTRL = 0xC7
ST7789_RDID1 = 0xDA
ST7789_RDID2 = 0xDB
ST7789_RDID3 = 0xDC
ST7789_RDID4 = 0xDD
ST7789_GMCTRP1 = 0xE0
ST7789_GMCTRN1 = 0xE1
ST7789_PWCTR6 = 0xFC
class ST7789(object):
"""Representation of an ST7789 TFT LCD."""
def __init__(self, port, cs, dc, backlight=None, rst=None, width=240,
height=240, rotation=90, invert=True, spi_speed_hz=4000000,
offset_left=0,
offset_top=0):
"""Create an instance of the display using SPI communication.
Must provide the GPIO pin number for the D/C pin and the SPI driver.
Can optionally provide the GPIO pin number for the reset pin as the rst parameter.
:param port: SPI port number
:param cs: SPI chip-select number (0 or 1 for BCM
:param backlight: Pin for controlling backlight
:param rst: Reset pin for ST7789
:param width: Width of display connected to ST7789
:param height: Height of display connected to ST7789
:param rotation: Rotation of display connected to ST7789
:param invert: Invert display
:param spi_speed_hz: SPI speed (in Hz)
"""
if rotation not in [0, 90, 180, 270]:
raise ValueError("Invalid rotation {}".format(rotation))
if width != height and rotation in [90, 270]:
raise ValueError("Invalid rotation {} for {}x{} resolution".format(rotation, width, height))
# GPIO.setwarnings(False)
# GPIO.setmode(GPIO.BCM)
self._spi = spidev.SpiDev(port, cs)
self._spi.mode = 0
self._spi.lsbfirst = False
self._spi.max_speed_hz = spi_speed_hz
self._dc = dc
self._rst = rst
self._width = width
self._height = height
self._rotation = rotation
self._invert = invert
self._offset_left = offset_left
self._offset_top = offset_top
# Set DC as output.
# GPIO.setup(dc, GPIO.OUT)
# Setup backlight as output (if provided).
self._backlight = backlight
if backlight is not None:
# GPIO.setup(backlight, GPIO.OUT)
# GPIO.output(backlight, GPIO.LOW)
# time.sleep(0.1)
# GPIO.output(backlight, GPIO.HIGH)
pass
# Setup reset as output (if provided).
if rst is not None:
# GPIO.setup(rst, GPIO.OUT)
pass
self.reset()
self._init()
def send(self, data, is_data=True, chunk_size=4096):
"""Write a byte or array of bytes to the display. Is_data parameter
controls if byte should be interpreted as display data (True) or command
data (False). Chunk_size is an optional size of bytes to write in a
single SPI transaction, with a default of 4096.
"""
# Set DC low for command, high for data.
# GPIO.output(self._dc, is_data)
if is_data:
isdata='dh'
else:
isdata='dl'
msg = 'pinctrl set '+ str(self._dc) + ' op ' + isdata
subprocess.run(msg,shell=True)
# Convert scalar argument to list so either can be passed as parameter.
if isinstance(data, numbers.Number):
data = [data & 0xFF]
# Write data a chunk at a time.
for start in range(0, len(data), chunk_size):
end = min(start + chunk_size, len(data))
self._spi.xfer(data[start:end])
def set_backlight(self, value):
"""Set the backlight on/off."""
if self._backlight is not None:
# GPIO.output(self._backlight, value)
pass
@property
def width(self):
return self._width if self._rotation == 0 or self._rotation == 180 else self._height
@property
def height(self):
return self._height if self._rotation == 0 or self._rotation == 180 else self._width
def command(self, data):
"""Write a byte or array of bytes to the display as command data."""
self.send(data, False)
def data(self, data):
"""Write a byte or array of bytes to the display as display data."""
self.send(data, True)
def reset(self):
print("Reset the display, if reset pin is connected.")
if self._rst is not None:
msg = 'pinctrl set '+ str(self._rst) + ' op dh'
# msg = 'pinctrl set 25 op dh'
subprocess.run(msg,shell=True)
time.sleep(0.500)
msg = 'pinctrl set '+ str(self._rst) + ' op dl'
# msg = 'pinctrl set 25 op dl'
subprocess.run(msg,shell=True)
time.sleep(0.500)
msg = 'pinctrl set '+ str(self._rst) + ' op dh'
# msg = 'pinctrl set 25 op dh'
subprocess.run(msg,shell=True)
time.sleep(0.500)
def _init(self):
# Initialize the display.
self.command(ST7789_SWRESET) # Software reset
time.sleep(0.150) # delay 150 ms
self.command(ST7789_MADCTL)
self.data(0x70)
self.command(ST7789_FRMCTR2) # Frame rate ctrl - idle mode
self.data(0x0C)
self.data(0x0C)
self.data(0x00)
self.data(0x33)
self.data(0x33)
self.command(ST7789_COLMOD)
self.data(0x05)
self.command(ST7789_GCTRL)
self.data(0x14)
self.command(ST7789_VCOMS)
self.data(0x37)
self.command(ST7789_LCMCTRL) # Power control
self.data(0x2C)
self.command(ST7789_VDVVRHEN) # Power control
self.data(0x01)
self.command(ST7789_VRHS) # Power control
self.data(0x12)
self.command(ST7789_VDVS) # Power control
self.data(0x20)
self.command(0xD0)
self.data(0xA4)
self.data(0xA1)
self.command(ST7789_FRCTRL2)
self.data(0x0F)
self.command(ST7789_GMCTRP1) # Set Gamma
self.data(0xD0)
self.data(0x04)
self.data(0x0D)
self.data(0x11)
self.data(0x13)
self.data(0x2B)
self.data(0x3F)
self.data(0x54)
self.data(0x4C)
self.data(0x18)
self.data(0x0D)
self.data(0x0B)
self.data(0x1F)
self.data(0x23)
self.command(ST7789_GMCTRN1) # Set Gamma
self.data(0xD0)
self.data(0x04)
self.data(0x0C)
self.data(0x11)
self.data(0x13)
self.data(0x2C)
self.data(0x3F)
self.data(0x44)
self.data(0x51)
self.data(0x2F)
self.data(0x1F)
self.data(0x1F)
self.data(0x20)
self.data(0x23)
if self._invert:
self.command(ST7789_INVON) # Invert display
else:
self.command(ST7789_INVOFF) # Don't invert display
self.command(ST7789_SLPOUT)
self.command(ST7789_DISPON) # Display on
time.sleep(0.100) # 100 ms
def begin(self):
"""Set up the display
Deprecated. Included in __init__.
"""
pass
def set_window(self, x0=0, y0=0, x1=None, y1=None):
"""Set the pixel address window for proceeding drawing commands. x0 and
x1 should define the minimum and maximum x pixel bounds. y0 and y1
should define the minimum and maximum y pixel bound. If no parameters
are specified the default will be to update the entire display from 0,0
to width-1,height-1.
"""
if x1 is None:
x1 = self._width - 1
if y1 is None:
y1 = self._height - 1
y0 += self._offset_top
y1 += self._offset_top
x0 += self._offset_left
x1 += self._offset_left
self.command(ST7789_CASET) # Column addr set
self.data(x0 >> 8)
self.data(x0 & 0xFF) # XSTART
self.data(x1 >> 8)
self.data(x1 & 0xFF) # XEND
self.command(ST7789_RASET) # Row addr set
self.data(y0 >> 8)
self.data(y0 & 0xFF) # YSTART
self.data(y1 >> 8)
self.data(y1 & 0xFF) # YEND
self.command(ST7789_RAMWR) # write to RAM
def display(self, image):
"""Write the provided image to the hardware.
:param image: Should be RGB format and the same dimensions as the display hardware.
"""
# Set address bounds to entire display.
self.set_window()
# Convert image to 16bit RGB565 format and
# flatten into bytes.
pixelbytes = self.image_to_data(image, self._rotation)
# Write data to hardware.
for i in range(0, len(pixelbytes), 4096):
self.data(pixelbytes[i:i + 4096])
def image_to_data(self, image, rotation=0):
if not isinstance(image, np.ndarray):
image = np.array(image.convert('RGB'))
# Rotate the image
pb = np.rot90(image, rotation // 90).astype('uint16')
# Mask and shift the 888 RGB into 565 RGB
red = (pb[..., [0]] & 0xf8) << 8
green = (pb[..., [1]] & 0xfc) << 3
blue = (pb[..., [2]] & 0xf8) >> 3
# Stick 'em together
result = red | green | blue
# Output the raw bytes
return result.byteswap().tobytes()
実行します。
(envtft) yoshi@ras05:~ $ python st7789a.py
Hello World!
めでたく動きました。
