ST7789 Driver for MicroPython
This driver is based on devbis' st7789_mpy driver. I modified the original driver for one of my projects to add:
- Display Rotation.
- Scrolling
- Writing text using bitmaps converted from True Type fonts
- Drawing text using 8 and 16 bit wide bitmap fonts
- Drawing text using Hershey vector fonts
- Drawing JPG's, including a SLOW mode to draw jpg's larger than available ram using the TJpgDec - Tiny JPEG Decompressor R0.01d. from http://elm-chan.org/fsw/tjpgd/00index.html
- Drawing and rotating Polygons and filled Polygons.
- Tracking bounds
- Support for st7735 displays
Included are 12 bitmap fonts derived from classic pc text mode fonts, 26 Hershey vector fonts and several example programs for different devices.
Display Configuration
Some displays may use a BGR color order or iverted colors. The cfg_helper.py
program can use used to determine the color order, inversion_mode, colstart, and rowstart values needed for a display.
Color Modes
You can test the color order needed by a display by filling the display with the st7789.RED
color and observing the color displayed.
- If the display is RED, the settings are correct.
- If the display is BLUE,
color_order
should best7789.BGR
. - If the display is YELLOW,
inversion_mode
should beTrue
. - If the display is CYAN,
color_order
should best7789.BGR
andinversion_mode
should beTrue
.
colstart and rowstart
Some displays have a frame buffer memory larger than the physical LCD or LED matrix. In these cases the driver must be configured with the position of the first physcial column and row pixels relative to the frame buffer. Each rotation setting of the display may require different colstart and rowstart values.
The driver automatically adjusts the colstart and rowstarts values for common 135x240, 240x240 and
240x320 displays. These values can be overridden using the offsets
method if the default values do not work for your display. The offsets
method should be called after any calls of the rotation
method.
128x128 st7735 cfg_helper.py example
inversion_mode(False)
color_order = st7789.BGR
for rotation 0 use offset(2, 1)
for rotation 1 use offset(1, 2)
for rotation 2 use offset(2, 3)
for rotation 3 use offset(3, 2)
128x160 st7735 cfg_helper.py example
inversion_mode(False)
color_order = st7789.RGB
for rotation 0 use offset(0, 0)
for rotation 1 use offset(0, 0)
for rotation 2 use offset(0, 0)
for rotation 3 use offset(0, 0)
Pre-compiled firmware files
The firmware directory contains pre-compiled firmware for various devices with the st7789 C driver and frozen python font files. See the README.md file in the fonts folder for more information on the font files.
MicroPython MicroPython v1.18-56-g517e82eb6 compiled with ESP IDF v4.2 using CMake
Directory | File | Device |
---|---|---|
GENERIC-7789 | firmware.bin | Generic ESP32 devices |
GENERIC_SPIRAM-7789 | firmware.bin | Generic ESP32 devices with SPI Ram |
GENERIC_C3 | firmware.bin | Generic ESP32-C3 devices (JPG support not working) |
PYBV11 | firmware.dfu | Pyboard v1.1 |
RP2 | firmware.uf2 | Raspberry Pi Pico RP2040 |
T-DISPLAY | firmware.bin | LILYGO® TTGO T-Display |
T-Watch-2020 | firmware.bin | LILYGO® T-Watch 2020 |
Additional Modules
Module | Source |
---|---|
axp202c | https://github.com/lewisxhe/AXP202X_Libraries |
focaltouch | https://gitlab.com/mooond/t-watch2020-esp32-with-micropython |
Video Examples
Example | Video |
---|---|
PYBV11 hello.py | https://youtu.be/OtcERmad5ps |
PYBV11 scroll.py | https://youtu.be/ro13rvaLKAc |
T-DISPLAY fonts.py | https://youtu.be/2cnAhEucPD4 |
T-DISPLAY hello.py | https://youtu.be/z41Du4GDMSY |
T-DISPLAY scroll.py | https://youtu.be/GQa-RzHLBak |
T-DISPLAY roids.py | https://youtu.be/JV5fPactSPU |
TWATCH-2020 draw.py | https://youtu.be/O_lDBnvH1Sw |
TWATCH-2020 hello.py | https://youtu.be/Bwq39tuMoY4 |
TWATCH-2020 bitmap.py | https://youtu.be/DgYzgnAW2d8 |
TWATCH-2020 watch.py | https://youtu.be/NItKb6umMc4 |
This is a work in progress.
Thanks go out to:
- https://github.com/devbis for the original driver this is based on.
- https://github.com/hklang10 for letting me know of the new mp_raise_ValueError().
- https://github.com/aleggon for finding the correct offsets for a 240x240 display and discovering issues compiling for STM32 based boards.
-- Russ
Overview
This is a driver for MicroPython to handle cheap displays based on the ST7789 chip.
The driver is written in C. Firmware is provided for ESP32, ESP32 with SPIRAM, pyboard1.1, and Raspberry Pi Pico devices.
Setup MicroPython Build Environment in Ubuntu 20.04.2
See the MicroPython README.md if you run into any build issues not directly related to the st7789 driver. The recommended MicroPython build instructions may have changed.
Update and upgrade Ubuntu using apt-get if you are using a new install of Ubuntu or the Windows Subsystem for Linux.
sudo apt-get -y update
sudo apt-get -y upgrade
Use apt-get to install the required build tools.
sudo apt-get -y install build-essential libffi-dev git pkg-config cmake virtualenv python3-pip python3-virtualenv
Install a compatible esp-idf SDK
The MicroPython README.md states: "The ESP-IDF changes quickly and MicroPython only supports certain versions. Currently MicroPython supports v4.0.2, v4.1.1 and v4.2, although other IDF v4 versions may also work." I have had good luck using IDF v4.2.
Clone the esp-idf SDK repo -- this usually takes several minutes
git clone -b v4.2 --recursive https://github.com/espressif/esp-idf.git
cd esp-idf/
git pull
If you already have a copy of the IDF you can checkout a version compatible with MicroPython and update the submodules using:
$ cd esp-idf
$ git checkout v4.2
$ git submodule update --init --recursive
Install the esp-idf SDK.
./install.sh
Source the esp-idf export.sh script to set the required environment variables. It's important that you source the file and not run it using ./export.sh. You will need to source this file before compiling MicroPython.
source export.sh
cd ..
Clone the MicroPython repo.
git clone https://github.com/micropython/micropython.git
Clone the st7789 driver repo.
git clone https://github.com/russhughes/st7789_mpy.git
Update the git submodules and compile the micropython cross-compiler
cd micropython/
git submodule update --init
cd mpy-cross/
make
cd ..
cd ports/esp32
Copy any .py files you want to include in the firmware as frozen python modules to the modules subdirectory in ports/esp32. Be aware there is a limit to the flash space available. You will know you have exceeded this limit if you receive an error message saying the code won't fit in the partition or if your firmware continuously reboots with an error.
For example:
cp ../../../st7789_mpy/fonts/bitmap/vga1_16x16.py modules
cp ../../../st7789_mpy/fonts/truetype/NotoSans_32.py modules
cp ../../../st7789_mpy/fonts/vector/scripts.py modules
Build the MicroPython firmware with the driver and frozen .py files in the modules directory. If you did not add any .py files to the modules directory you can leave out the FROZEN_MANIFEST and FROZEN_MPY_DIR settings.
make USER_C_MODULES=../../../../st7789_mpy/st7789/micropython.cmake FROZEN_MANIFEST="" FROZEN_MPY_DIR=$UPYDIR/modules
Erase and flash the firmware to your device. Set PORT= to the ESP32's usb serial port. I could not get the usb serial port to work under the Windows Subsystem (WSL2) for Linux. If you have the same issue you can copy the firmware.bin file and use the Windows esptool.py to flash your device.
make USER_C_MODULES=../../../../st7789_mpy/st7789/micropython.cmake PORT=/dev/ttyUSB0 erase
make USER_C_MODULES=../../../../st7789_mpy/st7789/micropython.cmake PORT=/dev/ttyUSB0 deploy
The firmware.bin file will be in the build-GENERIC directory. To flash using the python esptool.py utility. Use pip3 to install the esptool if it's not already installed.
pip3 install esptool
Set PORT= to the ESP32's usb serial port
esptool.py --port COM3 erase_flash
esptool.py --chip esp32 --port COM3 write_flash -z 0x1000 firmware.bin
CMake building instructions for MicroPython 1.14 and later
for ESP32:
$ cd micropython/ports/esp32
And then compile the module with specified USER_C_MODULES dir
$ make USER_C_MODULES=../../../../st7789_mpy/st7789/micropython.cmake
for Raspberry Pi PICO:
$ cd micropython/ports/rp2
And then compile the module with specified USER_C_MODULES dir
$ make USER_C_MODULES=../../../st7789_mpy/st7789/micropython.cmake
Working examples
This module was tested on ESP32, STM32 based pyboard v1.1 and the Raspberry Pi
Pico. You have to provide a SPI
object and the pin to use for the `dc' input of the screen.
# ESP32
import machine
import st7789
spi = machine.SPI(2, baudrate=40000000, polarity=1, sck=machine.Pin(18), mosi=machine.Pin(23))
display = st7789.ST7789(spi, 240, 240, reset=machine.Pin(4, machine.Pin.OUT), dc=machine.Pin(2, machine.Pin.OUT))
display.init()
I was not able to run the display with a baud rate over 40MHZ.
Methods
-
st7789.ST7789(spi, width, height, dc, reset, cs, backlight, rotations, rotation, color_order, inversion, options, buffer_size)
Required positional arguments:
spi
spi devicewidth
display widthheight
display height
Required keyword arguments:
dc
sets the pin connected to the display data/command selection input. This parameter is always required.
Optional keyword arguments:
-
reset
sets the pin connected to the displays hardware reset input. If the displays reset pin is tied high thereset
parameter is not required. -
cs
sets the pin connected to the displays chip select input. If the displays CS pin is tied low, the display must be the only device connected to the SPI port. The display will always be the selected device and thecs
parameter is not required. -
backlight
sets the pin connected to the displays backlight enable input. The displays backlight input can often be left floating or disconnected as the backlight on some displays are always powered on and cannot be turned off. -
rotations
sets the orientation table. The orientation table is a list of tuples for eachrotation
that defines the MADCTL register, width, height, start_x, and start_y values.Default
rotations
are included for the following st7789 and st7735 display sizes:Display Default Orientation Tables 240x320 [(0x00, 240, 320, 0, 0), (0x60, 320, 240, 0, 0), (0xc0, 240, 320, 0, 0), (0xa0, 320, 240, 0, 0)] 240x240 [(0x00, 240, 240, 0, 0), (0x60, 240, 240, 0, 0), (0xc0, 240, 240, 0, 80), (0xa0, 240, 240, 80, 0)] 135x240 [(0x00, 135, 240, 52, 40), (0x60, 240, 135, 40, 53), (0xc0, 135, 240, 53, 40), (0xa0, 240, 135, 40, 52)] 128x160 [(0x00, 128, 160, 0, 0), (0x60, 160, 128, 0, 0), (0xc0, 128, 160, 0, 0), (0xa0, 160, 128, 0, 0)] 128x128 [(0x00, 128, 128, 2, 1), (0x60, 128, 128, 1, 2), (0xc0, 128, 128, 2, 3), (0xa0, 128, 128, 3, 2)] other [(0x00, width, height, 0, 0)] You may define as many rotations in the list as you wish.
-
rotation
sets the display rotation according to the orientation table. The default orientation table defines four counter-clockwise rotations as 0-Portrait (0 degrees), 1- Landscape (90 degrees), 2- Reverse Portrait (180 degrees), and 3- Reverse Landscape (270 degrees) for 240x320, 240x240, 134x240, 128x160 and 128x128 displays with the LCD's ribbon cable at the bottom of the display. The default rotation being Portrait (0 degrees). -
color_order
set the color order used by the driver st7789.RGB and st7789.BGR are supported. -
inversion
Sets the display color inversion mode if True, clears the display color inversion mode if false. -
options
Sets driver option flags.Option Description st7789.WRAP pixels, lines, polygons and Hershey text will wrap around the display both horizontally and vertically. st7789.WRAP_H pixels, lines, polygons and Hershey text will wrap around the display horizontally. st7789.WRAP_V pixels, lines, polygons and Hershey text will wrap around the display vertically. -
buffer_size
If a buffer_size is not specified a dynamically allocated buffer is created and freed as needed. If a buffer_size is specified it must be large enough to contain the largest bitmap, font character and/or decoded JPG image used (Rows * Columns * 2 bytes, 16bit colors in RGB565 notation). Dynamic allocation is slower and can cause heap fragmentation so garbage collection (GC) should be enabled.
-
inversion_mode(bool)
Sets the display color inversion mode if True, clears the display color inversion mode if False. -
madctl(value)
Returns the current value of the MADCTL register. Optionally sets the MADCTL register if a value is passed to the method.Constant Name Value Description st7789.MADCTL_MY 0x80 Page Address Order st7789_MADCTL_MX 0x40 Column Address Order st7789_MADCTL_MV 0x20 Page/Column Order st7789_MADCTL_ML 0x10 Line Address Order st7789_MADCTL_MH 0x04 Display Data Latch Order st7789_RGB 0x00 RGB color order st7789_BGR 0x08 BGR color order -
init()
Must be called to initalize the display.
-
on()
Turn on the backlight pin if one was defined during init.
-
off()
Turn off the backlight pin if one was defined during init.
-
fill(color)
Fill the display with the specified color.
-
pixel(x, y, color)
Set the specified pixel to the given
color
. -
line(x0, y0, x1, y1, color)
Draws a single line with the provided
color
from (x0
,y0
) to (x1
,y1
). -
hline(x, y, length, color)
Draws a single horizontal line with the provided
color
andlength
in pixels. Along withvline
, this is a fast version with reduced number of SPI calls. -
vline(x, y, length, color)
Draws a single horizontal line with the provided
color
andlength
in pixels. -
rect(x, y, width, height, color)
Draws a rectangle from (
x
,y
) with corresponding dimensions -
fill_rect(x, y, width, height, color)
Fill a rectangle starting from (
x
,y
) coordinates -
circle(x, y, r, color)
Draws a circle with radius
r
centered at the (x
,y
) coordinates in the givencolor
. -
fill_circle(x, y, r, color)
Draws a filled circle with radius
r
centered at the (x
,y
) coordinates in the givencolor
. -
blit_buffer(buffer, x, y, width, height)
Copy bytes() or bytearray() content to the screen internal memory. Note: every color requires 2 bytes in the array
-
text(font, s, x, y[, fg, bg])
Write text to the display using the specified bitmap
font
with the coordinates as the upper-left corner of the text. The foreground and background colors of the text can be set by the optional argumentsfg
andbg
, otherwise the foreground color defaults toWHITE
and the background color defaults toBLACK
. See theREADME.md
in thefonts/bitmap
directory for example fonts. -
write(bitmap_font, s, x, y[, fg, bg, background_tuple, fill_flag])
Write text to the display using the specified proportional or Monospace bitmap font module with the coordinates as the upper-left corner of the text. The foreground and background colors of the text can be set by the optional arguments
fg
andbg
, otherwise the foreground color defaults toWHITE
and the background color defaults toBLACK
.Transparency can be emulated by providing a
background_tuple
containing (bitmap_buffer, width, height). This is the same format used by the jpg_decode method. See examples/T-DISPLAY/clock/clock.py for an example.See the
README.md
in thetruetype/fonts
directory for example fonts. Returns the width of the string as printed in pixels. Accepts UTF8 encoded strings.The
font2bitmap
utility creates compatible 1 bit per pixel bitmap modules from Proportional or Monospaced True Type fonts. The character size, foreground, background colors and the characters to include in the bitmap module may be specified as parameters. Use the -h option for details. If you specify a buffer_size during the display initialization it must be large enough to hold the widest character (HEIGHT * MAX_WIDTH * 2). -
write_len(bitap_font, s)
Returns the width of the string in pixels if printed in the specified font.
-
draw(vector_font, s, x, y[, fg, scale])
Draw text to the display using the specified hershey vector font with the coordinates as the lower-left corner of the text. The foreground color of the text can be set by the optional argument
fg
, otherwise the foreground color defaults toWHITE
. The size of the text can be scaled by specifying ascale
value. Thescale
value must be larger then 0 and can be a floating point or an integer value. Thescale
value defaults to 1.0. See the README.md in thevector/fonts
directory for example fonts and the utils directory for a font conversion program. -
draw_len(vector_font, s[, scale])
Returns the width of the string in pixels if drawn with the specified font.
-
jpg(jpg_filename, x, y [, method])
Draw JPG file on the display at the given
x
andy
coordinates as the upper left corner of the image. There memory required to decode and display a JPG can be considerable as a full screen 320x240 JPG would require at least 3100 bytes for the working area + 320 * 240 * 2 bytes of ram to buffer the image. Jpg images that would require a buffer larger than available memory can be drawn by passingSLOW
for method. TheSLOW
method will draw the image a piece at a time using the Minimum Coded Unit (MCU, typically a multiple of 8x8) of the image. -
jpg_decode(jpg_filename [, x, y, width, height])
Decode a jpg file and return it or a portion of it as a tuple composed of (buffer, width, height). The buffer is a color565 blit_buffer compatible byte array. The buffer will require width * height * 2 bytes of memory.
If the optional x, y, width and height parameters are given the buffer will only contain the specified area of the image. See examples/T-DISPLAY/clock/clock.py examples/T-DISPLAY/toasters_jpg/toasters_jpg.py for examples.
-
polygon_center(polygon)
Return the center of the
polygon
as an (x, y) tuple. Thepolygon
should consist of a list of (x, y) tuples forming a closed convex polygon. -
fill_polygon(polygon, x, y, color[, angle, center_x, center_y])
Draw a filled
polygon
at thex
,y
coordinates in thecolor
given. The polygon may be rotatedangle
radians about thecenter_x
andcenter_y
point. The polygon should consist of a list of (x, y) tuples forming a closed convex polygon.See the TWATCH-2020
watch.py
demo for an example. -
polygon(polygon, x, y, color, angle, center_x, center_y)
Draw a
polygon
at thex
,y
coordinates in thecolor
given. The polygon may be rotatedangle
radians a bout thecenter_x
andcenter_y
point. The polygon should consist of a list of (x, y) tuples forming a closed convex polygon.See the T-Display
roids.py
for an example. -
bounding({status, as_rect})
Bounding turns on and off tracking the area of the display that has been written to. Initially tracking is disabled, pass a True value to enable tracking and False to disable. Passing a True or False parameter will reset the current bounding rectangle to (display_width, display_height, 0, 0).
Returns a four integer tuple containing (min_x, min_y, max_x, max_y) indicating the area of the display that has been written to since the last clearing.
If
as_rect
parameter is True, the returned tuple will contain (min_x, min_y, width, height) values.See the TWATCH-2020
watch.py
demo for an example. -
bitmap(bitmap, x , y [, index])
Draw
bitmap
using the specifiedx
,y
coordinates as the upper-left corner of the of thebitmap
. The optionalindex
parameter provides a method to select from multiple bitmaps contained abitmap
module. Theindex
is used to calculate the offset to the beginning of the desired bitmap using the modules HEIGHT, WIDTH and BPP values.The
imgtobitmap.py
utility creates compatible 1 to 8 bit per pixel bitmap modules from image files using the Pillow Python Imaging Library.The
monofont2bitmap.py
utility creates compatible 1 to 8 bit per pixel bitmap modules from Monospaced True Type fonts. See theinconsolata_16.py
,inconsolata_32.py
andinconsolata_64.py
files in theexamples/lib
folder for sample modules and themono_font.py
program for an example using the generated modules.The character sizes, bit per pixel, foreground, background colors and the characters to include in the bitmap module may be specified as parameters. Use the -h option for details. Bits per pixel settings larger than one may be used to create antialiased characters at the expense of memory use. If you specify a buffer_size during the display initialization it must be large enough to hold the one character (HEIGHT * WIDTH * 2).
-
width()
Returns the current logical width of the display. (ie a 135x240 display rotated 90 degrees is 240 pixels wide)
-
height()
Returns the current logical height of the display. (ie a 135x240 display rotated 90 degrees is 135 pixels high)
-
rotation(r)
Set the rotates the logical display in a counter-clockwise direction. 0-Portrait (0 degrees), 1-Landscape (90 degrees), 2-Inverse Portrait (180 degrees), 3-Inverse Landscape (270 degrees)
-
offset(x_start, y_start)
The memory in the ST7789 controller is configured for a 240x320 display. When using a smaller display like a 240x240 or 135x240 an offset needs to added to the x and y parameters so that the pixels are written to the memory area that corresponds to the visible display. The offsets may need to be adjusted when rotating the display.For example the TTGO-TDisplay is 135x240 and uses the following offsets.
Rotation x_start y_start 0 52 40 1 40 53 2 53 40 3 40 52 When the rotation method is called the driver will adjust the offsets for a 135x240 or 240x240 display. Your display may require using different offset values, if so, use the
offset
method afterrotation
to set the offset values.The values needed for particular display may not be documented and may require some experimentation to determine the correct values. One technique is to draw a box the same size as the display and then make small changes to the offsets until the display looks correct. See the
cfg_helper.py
program in the examples folder for more information.
The module exposes predefined colors:
BLACK
, BLUE
, RED
, GREEN
, CYAN
, MAGENTA
, YELLOW
, and WHITE
Helper functions
-
color565(r, g, b)
Pack a color into 2-bytes rgb565 format
-
map_bitarray_to_rgb565(bitarray, buffer, width, color=WHITE, bg_color=BLACK)
Convert a
bitarray
to the rgb565 colorbuffer
that is suitable for blitting. Bit 1 inbitarray
is a pixel withcolor
and 0 - withbg_color
.This is a helper with a good performance to print text with a high resolution font. You can use an awesome tool https://github.com/peterhinch/micropython-font-to-py to generate a bitmap fonts from .ttf and use them as a frozen bytecode from the ROM memory.