QT Py 2040 and sh1106 display

[livinlowe2006]

Need some help with some example code Ive found:

# MicroPython SH1106 OLED driver, I2C and SPI interfaces
#
# The MIT License (MIT)
#
# Copyright (c) 2016 Radomir Dopieralski (@deshipu),
#               2017 Robert Hammelrath (@robert-hh)
#
# 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.
#
# Sample code sections
# ------------ SPI ------------------
# Pin Map SPI
#   - 3V3      - Vcc
#   - GND      - Gnd
#   - GPIO 11  - DIN / MOSI fixed
#   - GPIO 10  - CLK / Sck fixed
#   - GPIO 4   - CS (optional, if the only connected device, connect to GND)
#   - GPIO 5   - D/C
#   - GPIO 2   - Res
#
# for CS, D/C and Res other ports may be chosen.
#
# from machine import Pin, SPI
# import sh1106

# spi = SPI(1, baudrate=1000000)
# display = sh1106.SH1106_SPI(128, 64, spi, Pin(5), Pin(2), Pin(4))
# display.sleep(False)
# display.fill(0)
# display.text('Testing 1', 0, 0, 1)
# display.show()
#
# --------------- I2C ------------------
#
# Pin Map I2C
#   - 3V3      - Vcc
#   - GND      - Gnd
#   - GPIO 5   - CLK / SCL
#   - GPIO 4   - DIN / SDA
#   - GPIO 2   - Res
#   - GND      - CS
#   - GND      - D/C
#
#
# from machine import Pin, I2C
# import sh1106
#
# i2c = I2C(0, scl=Pin(5), sda=Pin(4), freq=400000)
# display = sh1106.SH1106_I2C(128, 64, i2c, Pin(2), 0x3c)
# display.sleep(False)
# display.fill(0)
# display.text('Testing 1', 0, 0, 1)
# display.show()

from micropython import const
import utime as time
import framebuf


# a few register definitions
_SET_CONTRAST        = const(0x81)
_SET_NORM_INV        = const(0xa6)
_SET_DISP            = const(0xae)
_SET_SCAN_DIR        = const(0xc0)
_SET_SEG_REMAP       = const(0xa0)
_LOW_COLUMN_ADDRESS  = const(0x00)
_HIGH_COLUMN_ADDRESS = const(0x10)
_SET_PAGE_ADDRESS    = const(0xB0)


class SH1106:
    def __init__(self, width, height, external_vcc):
        self.width = width
        self.height = height
        self.external_vcc = external_vcc
        self.pages = self.height // 8
        self.buffer = bytearray(self.pages * self.width)
        fb = framebuf.FrameBuffer(self.buffer, self.width, self.height,
                                  framebuf.MVLSB)
        self.framebuf = fb
# set shortcuts for the methods of framebuf
        self.fill = fb.fill
        self.fill_rect = fb.fill_rect
        self.hline = fb.hline
        self.vline = fb.vline
        self.line = fb.line
        self.rect = fb.rect
        self.pixel = fb.pixel
        self.scroll = fb.scroll
        self.text = fb.text
        self.blit = fb.blit

        self.init_display()

    def init_display(self):
        self.reset()
        self.fill(0)
        self.poweron()
        self.show()

    def poweroff(self):
        self.write_cmd(_SET_DISP | 0x00)

    def poweron(self):
        self.write_cmd(_SET_DISP | 0x01)

    def rotate(self, flag, update=True):
        if flag:
            self.write_cmd(_SET_SEG_REMAP | 0x01)  # mirror display vertically
            self.write_cmd(_SET_SCAN_DIR | 0x08)  # mirror display hor.
        else:
            self.write_cmd(_SET_SEG_REMAP | 0x00)
            self.write_cmd(_SET_SCAN_DIR | 0x00)
        if update:
            self.show()

    def sleep(self, value):
        self.write_cmd(_SET_DISP | (not value))

    def contrast(self, contrast):
        self.write_cmd(_SET_CONTRAST)
        self.write_cmd(contrast)

    def invert(self, invert):
        self.write_cmd(_SET_NORM_INV | (invert & 1))

    def show(self):
        for page in range(self.height // 8):
            self.write_cmd(_SET_PAGE_ADDRESS | page)
            self.write_cmd(_LOW_COLUMN_ADDRESS | 2)
            self.write_cmd(_HIGH_COLUMN_ADDRESS | 0)
            self.write_data(self.buffer[
                self.width * page:self.width * page + self.width
            ])

    def reset(self, res):
        if res is not None:
            res(1)
            time.sleep_ms(1)
            res(0)
            time.sleep_ms(20)
            res(1)
            time.sleep_ms(20)


class SH1106_I2C(SH1106):
    def __init__(self, width, height, i2c, res=None, addr=0x3c,
                 external_vcc=False):
        self.i2c = i2c
        self.addr = addr
        self.res = res
        self.temp = bytearray(2)
        if res is not None:
            res.init(res.OUT, value=1)
        super().__init__(width, height, external_vcc)

    def write_cmd(self, cmd):
        self.temp[0] = 0x80  # Co=1, D/C#=0
        self.temp[1] = cmd
        self.i2c.writeto(self.addr, self.temp)

    def write_data(self, buf):
        self.i2c.writeto(self.addr, b'\x40'+buf)

    def reset(self):
        super().reset(self.res)


class SH1106_SPI(SH1106):
    def __init__(self, width, height, spi, dc, res=None, cs=None,
                 external_vcc=False):
        self.rate = 10 * 1000 * 1000
        dc.init(dc.OUT, value=0)
        if res is not None:
            res.init(res.OUT, value=0)
        if cs is not None:
            cs.init(cs.OUT, value=1)
        self.spi = spi
        self.dc = dc
        self.res = res
        self.cs = cs
        super().__init__(width, height, external_vcc)

    def write_cmd(self, cmd):
        self.spi.init(baudrate=self.rate, polarity=0, phase=0)
        if self.cs is not None:
            self.cs(1)
            self.dc(0)
            self.cs(0)
            self.spi.write(bytearray([cmd]))
            self.cs(1)
        else:
            self.dc(0)
            self.spi.write(bytearray([cmd]))

    def write_data(self, buf):
        self.spi.init(baudrate=self.rate, polarity=0, phase=0)
        if self.cs is not None:
            self.cs(1)
            self.dc(1)
            self.cs(0)
            self.spi.write(buf)
            self.cs(1)
        else:
            self.dc(1)
            self.spi.write(buf)

    def reset(self):
        super().reset(self.res)```
and

```py

# Display Image & text on I2C driven SH1106 OLED display
from machine import I2C, ADC
from sh1106 import SH1106_I2C
import framebuf

WIDTH  = 128                                            # oled display width
HEIGHT = 64                                            # oled display height

i2c = I2C(0)                                            # Init I2C using I2C0 defaults, SCL=Pin(GP9), SDA=Pin(GP8), freq=400000
print("I2C Address      : "+hex(i2c.scan()[0]).upper()) # Display device address
print("I2C Configuration: "+str(i2c))                   # Display I2C config


oled = SH1106_I2C(WIDTH, HEIGHT, i2c)                  # Init oled display

# Raspberry Pi logo as 32x32 bytearray
buffer = bytearray(b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00|?\x00\x01\x86@\x80\x01\x01\x80\x80\x01\x11\x88\x80\x01\x05\xa0\x80\x00\x83\xc1\x00\x00C\xe3\x00\x00~\xfc\x00\x00L'\x00\x00\x9c\x11\x00\x00\xbf\xfd\x00\x00\xe1\x87\x00\x01\xc1\x83\x80\x02A\x82@\x02A\x82@\x02\xc1\xc2@\x02\xf6>\xc0\x01\xfc=\x80\x01\x18\x18\x80\x01\x88\x10\x80\x00\x8c!\x00\x00\x87\xf1\x00\x00\x7f\xf6\x00\x008\x1c\x00\x00\x0c \x00\x00\x03\xc0\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00")

# Load the raspberry pi logo into the framebuffer (the image is 32x32)
fb = framebuf.FrameBuffer(buffer, 32, 32, framebuf.MONO_HLSB)

# Clear the oled display in case it has junk on it.
oled.fill(0)

# Blit the image from the framebuffer to the oled display
oled.blit(fb, 96, 0)

# Add some text
oled.text("Raspberry Pi",5,5)
oled.text("Pico",5,15)

# Finally update the oled display so the image & text is displayed
oled.show()

I get the following output from thonny:

MPY: soft reboot
I2C Address : 0X3C
I2C Configuration: I2C(0, freq=399361, scl=25, sda=24, timeout=50000)
Traceback (most recent call last):
File "", line 14, in
File "sh1106.py", line 172, in init
File "sh1106.py", line 110, in init
File "sh1106.py", line 115, in init_display
File "sh1106.py", line 122, in poweron
File "sh1106.py", line 177, in write_cmd
OSError: [Errno 5] EIO

The 2040 can see the display, but from what I have found online the OSError usually means the 2040 doesnt have communication with the display. Can anyone help or give directions to look?

Thanks

[Josverl]

You can use GitHub Flavored Markdown to format your posts. In particular use 'triple backtick'
```py
# code goes here
``` around your code snippets to get syntax highlighting and proper indenting.
Also see the section https://github.com/orgs/micropython/discussions/9111

[robert-hh]

@livinlowe2006 It looks like a I2C communication problem. The most common problem are missing pull-up resistors. In that case scan() with it's 1 byte message may succeed, but transmission of longer messages fail. Check the presence of pull-up resistors. You could as well try to work with a very low freq setting as test. If that works, it also indicates a problem with the pull-up of SDA and SCL.
Sometimes people have issues because the display is simply of a different type. SH1106 are sometimes sold as SSD1306 and the opposite.
I have used the SH1106 driver with various ports & boards. It should be fine.

[livinlowe2006]

@Josverl Thank You! I cleaned up my post.
@robert-hh You were correct! Adding 10k pullups made the display work! Hope this post helps others!