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updated all to micropython

master
Jake 2026-07-25 23:06:47 +08:00
parent 1850bed768
commit 0ded6c003b
4 changed files with 343 additions and 172 deletions
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8
.vite/deps/_metadata.json Normal file
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{
"hash": "6f652a7d",
"configHash": "aba780af",
"lockfileHash": "e3b0c442",
"browserHash": "e137aec8",
"optimized": {},
"chunks": {}
}

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{
"type": "module"
}

164
files/ssd1306.py Normal file
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@ -0,0 +1,164 @@
# MicroPython SSD1306 OLED driver, I2C and SPI interfaces
from micropython import const
import framebuf
# register definitions
SET_CONTRAST = const(0x81)
SET_ENTIRE_ON = const(0xA4)
SET_NORM_INV = const(0xA6)
SET_DISP = const(0xAE)
SET_MEM_ADDR = const(0x20)
SET_COL_ADDR = const(0x21)
SET_PAGE_ADDR = const(0x22)
SET_DISP_START_LINE = const(0x40)
SET_SEG_REMAP = const(0xA0)
SET_MUX_RATIO = const(0xA8)
SET_IREF_SELECT = const(0xAD)
SET_COM_OUT_DIR = const(0xC0)
SET_DISP_OFFSET = const(0xD3)
SET_COM_PIN_CFG = const(0xDA)
SET_DISP_CLK_DIV = const(0xD5)
SET_PRECHARGE = const(0xD9)
SET_VCOM_DESEL = const(0xDB)
SET_CHARGE_PUMP = const(0x8D)
# Subclassing FrameBuffer provides support for graphics primitives
# http://docs.micropython.org/en/latest/pyboard/library/framebuf.html
class SSD1306(framebuf.FrameBuffer):
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)
super().__init__(self.buffer, self.width, self.height, framebuf.MONO_VLSB)
self.init_display()
def init_display(self):
for cmd in (
SET_DISP, # display off
# address setting
SET_MEM_ADDR,
0x00, # horizontal
# resolution and layout
SET_DISP_START_LINE, # start at line 0
SET_SEG_REMAP | 0x01, # column addr 127 mapped to SEG0
SET_MUX_RATIO,
self.height - 1,
SET_COM_OUT_DIR | 0x08, # scan from COM[N] to COM0
SET_DISP_OFFSET,
0x00,
SET_COM_PIN_CFG,
0x02 if self.width > 2 * self.height else 0x12,
# timing and driving scheme
SET_DISP_CLK_DIV,
0x80,
SET_PRECHARGE,
0x22 if self.external_vcc else 0xF1,
SET_VCOM_DESEL,
0x30, # 0.83*Vcc
# display
SET_CONTRAST,
0xFF, # maximum
SET_ENTIRE_ON, # output follows RAM contents
SET_NORM_INV, # not inverted
SET_IREF_SELECT,
0x30, # enable internal IREF during display on
# charge pump
SET_CHARGE_PUMP,
0x10 if self.external_vcc else 0x14,
SET_DISP | 0x01, # display on
): # on
self.write_cmd(cmd)
self.fill(0)
self.show()
def poweroff(self):
self.write_cmd(SET_DISP)
def poweron(self):
self.write_cmd(SET_DISP | 0x01)
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 rotate(self, rotate):
self.write_cmd(SET_COM_OUT_DIR | ((rotate & 1) << 3))
self.write_cmd(SET_SEG_REMAP | (rotate & 1))
def show(self):
x0 = 0
x1 = self.width - 1
if self.width != 128:
# narrow displays use centred columns
col_offset = (128 - self.width) // 2
x0 += col_offset
x1 += col_offset
self.write_cmd(SET_COL_ADDR)
self.write_cmd(x0)
self.write_cmd(x1)
self.write_cmd(SET_PAGE_ADDR)
self.write_cmd(0)
self.write_cmd(self.pages - 1)
self.write_data(self.buffer)
class SSD1306_I2C(SSD1306):
def __init__(self, i2c, addr=0x3C, external_vcc=False):
self.i2c = i2c
self.addr = addr
self.temp = bytearray(2)
self.write_list = [b"\x40", None] # Co=0, D/C#=1
super().__init__(128, 64, 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.write_list[1] = buf
self.i2c.writevto(self.addr, self.write_list)
class SSD1306_SPI(SSD1306):
def __init__(self, width, height, spi, dc, res, cs, external_vcc=False):
self.rate = 10 * 1024 * 1024
dc.init(dc.OUT, value=0)
res.init(res.OUT, value=0)
cs.init(cs.OUT, value=1)
self.spi = spi
self.dc = dc
self.res = res
self.cs = cs
import time
self.res(1)
time.sleep_ms(1)
self.res(0)
time.sleep_ms(10)
self.res(1)
super().__init__(width, height, external_vcc)
def write_cmd(self, cmd):
self.spi.init(baudrate=self.rate, polarity=0, phase=0)
self.cs(1)
self.dc(0)
self.cs(0)
self.spi.write(bytearray([cmd]))
self.cs(1)
def write_data(self, buf):
self.spi.init(baudrate=self.rate, polarity=0, phase=0)
self.cs(1)
self.dc(1)
self.cs(0)
self.spi.write(buf)
self.cs(1)

340
index.html
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@ -24,7 +24,7 @@
<button class="tab-btn text-gray-600 hover:text-blue-600" data-target="lesson2">Uploading Code</button>
<button class="tab-btn text-gray-600 hover:text-blue-600" data-target="lesson3">Motors</button>
<button class="tab-btn text-gray-600 hover:text-blue-600" data-target="lesson4">Color Sensors</button>
<button class="tab-btn text-gray-600 hover:text-blue-600" data-target="lesson5">I2C Multiplexing</button>
<button class="tab-btn text-gray-600 hover:text-blue-600 hidden" data-target="lesson5">I2C Multiplexing</button>
<button class="tab-btn text-gray-600 hover:text-blue-600" data-target="lesson6">OLED Display</button>
<button class="tab-btn text-gray-600 hover:text-blue-600" data-target="lesson7">RGB LED(Neopixel)</button>
<button class="tab-btn text-gray-600 hover:text-blue-600" data-target="lesson8">Sonar</button>
@ -226,6 +226,7 @@ motorIN2.duty_u16(0) </code></pre>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
from machine import Pin, PWM
import time
# Initialize motor PWM pins
motorIN1 = PWM(Pin(8))
@ -235,7 +236,7 @@ def motor(power):
# Make sure power is never greater than 100 or less than -100
if power > 100:
power = 100
elif power < -100:
elif power &lt; -100:
power = -100
# Convert 0-100 value, to 0 to 65535
@ -245,7 +246,7 @@ def motor(power):
if power > 0:
motorIN1.duty_u16(duty)
motorIN2.duty_u16(0)
elif power < 0:
elif power &lt; 0:
motorIN1.duty_u16(0)
motorIN2.duty_u16(duty)
else:
@ -273,7 +274,7 @@ for i in range(-100, 100):
motor code into a new module.</p>
</br>
<p>We make a second file called <code>motor.py</code> which we'll import and call from our main
<code>code.py</code> file.
<code>main.py</code> file.
</p>
<p>Now all we need to do from the main code is:</p>
</br>
@ -293,7 +294,7 @@ for i in range(-100, 100):
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm">
<code class="language-python">
# code.py
# main.py
import time
import motor
@ -312,6 +313,8 @@ for i in range(-100, 100):
print(i)
time.sleep(0.1)
</code></pre>
</br>
<pre class="bg-gray-100 p-4 rounded shadow text-sm">
@ -334,7 +337,7 @@ class Motor:
# Constrain power to -100 to 100
if power > 100:
power = 100
elif power < -100:
elif power &lt; -100:
power = -100
# Scale to duty cycle (0–65535 for RP2040)
@ -343,7 +346,7 @@ class Motor:
if power > 0:
self.in1.duty_u16(duty)
self.in2.duty_u16(0)
elif power < 0:
elif power &lt; 0:
self.in1.duty_u16(0)
self.in2.duty_u16(duty)
else:
@ -410,51 +413,41 @@ class Motor:
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
# color.py
import struct
import time
class Color:
def __init__(self, bus, address=0x29):
self._bus = bus
self._i2c_address = address
self._bus.writeto(self._i2c_address, b'\x80\x03')
self._bus.writeto(self._i2c_address, b'\x81\x2b')
self._bus.writeto(self._i2c_address, b'\x81\xFF') # Integration time 0xFF=2.4ms 0xF0=38.4ms 0x00=614.4ms
self._bus.writeto(self._i2c_address, b'\x8F\x02') # Gain 0x00=1x, 0x01=4x 0.02=16x, 0x03=60x
TCS_ADDR = 0x29
COMMAND_BIT = 0x80
def scaled(self):
crgb = self.raw()
if crgb[0] > 0:
return tuple(float(x) / crgb[0] for x in crgb[1:])
def i2c_locked(i2c, func, *args, **kwargs):
"""Wraps I2C operations with lock acquisition and release."""
while not i2c.try_lock():
pass
try:
return func(*args, **kwargs)
finally:
i2c.unlock()
return (0,0,0)
def write_register(i2c, addr, reg, value):
"""Writes a byte to a register."""
i2c_locked(i2c, i2c.writeto, addr, bytes([COMMAND_BIT | reg, value]))
def rgb(self):
return tuple(int(x * 255) for x in self.scaled())
def read_register(i2c, addr, reg, length):
"""Reads multiple bytes from a register."""
result = bytearray(length)
def light(self):
return self.raw()[0]
def brightness(self, level=65.535):
return int((self.light() / level))
def transfer():
i2c.writeto(addr, bytes([COMMAND_BIT | reg]))
i2c.readfrom_into(addr, result)
return result
def valid(self):
self._bus.writeto(self._i2c_address, b'\x93')
return self._bus.readfrom(self._i2c_address, 1)[0] & 1
return i2c_locked(i2c, transfer)
def raw(self):
self._bus.writeto(self._i2c_address, b'\xb4')
return struct.unpack("&lt;HHHH", self._bus.readfrom(self._i2c_address, 8))
def init_sensor(i2c):
time.sleep(0.01)
write_register(i2c, TCS_ADDR, 0x00, 0x01) # Enable (POWER ON)
time.sleep(0.01)
write_register(i2c, TCS_ADDR, 0x00, 0x03) # Enable (COLOR SENSING ON)
write_register(i2c, TCS_ADDR, 0x01, 0xFF) # Integration time 0xFF=2.4ms 0xF0=38.4ms 0x00=614.4ms
write_register(i2c, TCS_ADDR, 0x0F, 0x03) # Gain 0x00=1x, 0x01=4x 0.02=16x, 0x03=60x
def read_rgbc(i2c):
data = read_register(i2c, TCS_ADDR, 0x14, 8)
c = data[1] << 8 | data[0]
r = data[3] << 8 | data[2]
g = data[5] << 8 | data[4]
b = data[7] << 8 | data[6]
return r, g, b, c
</code></pre>
@ -462,73 +455,111 @@ def read_rgbc(i2c):
<!-- Step 3 -->
<div class="prose">
<h2>Step 3: code.py</h2>
<h2>Step 3: main.py</h2>
<p>Finally, this is how we call our color.py code from our main code, initialise and read the
sensor.</p>
</br>
<p>We use the <code>busio</code> library to handle our i2c. We initialise the connection by telling
<p>We use <code>I2C and Pin</code> from the <code>machine></code>library to handle our i2c. We initialise the connection by telling
it which pins we're using for SCL and SDA, and how fast to communicate.</p>
</br>
<p>We then pass on that connection to initialize the sensor using
<code>color.init_sensor(i2c)</code>
<code>color.Color(i2c)</code>
</p>
</br>
<p>The whenever we read <code>color.read_rgbc(i2c)</code> it will give us an array with the
<code>[red, green, blue, color]</code>, with the color being the total light reflected, rather
than just a single color.
<p>The whenever we read <code>color.rgb()</code> it will give us an array with the
<code>[red, green, blue]</code>.
</p>
<p>If we want to read the transparent sensor and get the total brightness, we call <code>color.light()</code></p>
</div>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
# code.py
# main.py
import busio
import time
import board
from machine import Pin, I2C
import color
i2c = busio.I2C(scl=board.GP1, sda=board.GP0, frequency=1_000_000)
color.init_sensor(i2c)
i2c = I2C(0, scl=Pin(1), sda=Pin(0))
rc = color.Color(i2c)
while True:
value = color.read_rgbc(i2c)
print(value)
time.sleep(0.1) </code></pre>
rgb = rc.rgb()
brightness = rc.light()
print(rgb, brightness)
time.sleep(0.1)
</code></pre>
</div>
<!-- Step 3 -->
<!-- Step 4 -->
<div class="prose">
<h2>Step 4: How to use it?</h2>
<p>To take these numbers and use them effectively, we need to break out the different colour
channels.</p>
</br>
<p>To the right is an example of how we might take the total colour from the result, and then use it
<p>To take these numbers and use them effectively, it depends on what we want to do.</p>
<p>TO follow a black line on a white background we only need the total brightness so we use the color.light() function.</p>
</br>ke the total colour from the result, and then use it
to decide whether to turn or not.</p>
</div>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm">
<code class="language-python">
value = color.read_rgbc(i2c) # Read the sensor [r,g,b,c]
# Extract each of the color values from the array
r = value[0] # red
g = value[1] # green
b = value[2] # blue
c = value[3] # all colors
value = rc.light() # Read the sensor
if c > 30: # If the c value is greater than 30
if value > 700: # If the value is greater than 700
# Turn Right
left_motor.move(50)
left_motor.move(-50)
right_motor.move(-50)
else:
# Go Straight
left_motor.move(50)
left_motor.move(50)
right_motor.move(50)
</code></pre>
</div>
<!-- Step 5 -->
<div class="prose">
<h2>Step 5: Adding a second sensor</h2>
<p>One sensor can follow an edge, but for a proper line follower we want a <code>left</code> and a
<code>right</code> sensor.
</p>
</br>
<p>There's a catch: every TCS3472 colour sensor uses the same I2C address (<code>0x29</code>). If you
wire both straight to the same SDA and SCL pins, they'll both answer every message and the
readings will be garbage.</p>
</br>
<p>The fix is to have a second I2C bus, luckily the RP2040 supports this.</p>
</br>
<p>We need to go back to our i2c declaration and add a channel number to it, <code>i2c = I2C(0, scl=Pin(1), sda=Pin(0))</code></p>
</br>
<p>That extra "0" specifically tells the RP2040 to use the first I2C bus. Then we can add a second bus by running <code>i2c2 = I2C(1, scl=Pin(3), sda=Pin(2))</code></p>
<p>Once we've initialized our right colour sensor with <code>rc = color.Color(i2c2)</code> then we're good to go!</code></p>
</div>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
# main.py
from machine import Pin, I2C
import time
import color
i2c = I2C(0, scl=Pin(1), sda=Pin(0)) # Initialize the first I2C bus
i2c2 = I2C(1, scl=Pin(3), sda=Pin(2)) # Initialize the second I2C bus
lc = color.Color(i2c2) # Initialize the left colour sensor
rc = color.Color(i2c) # Initialize the right colour sensor
while True:
left_color = lc.light()
right_color = rc.light()
print(left_color, right_color)
time.sleep(0.1)
</code></pre>
</div>
</div>
</section>
<!-- Lesson 5 (hidden initially) -->
@ -595,9 +626,9 @@ def i2c_locked(i2c, func, *args, **kwargs):
def select_channel(i2c, channel):
"""Selects the TCA9548A multiplexer channel."""
if not 0 <= channel <= 7:
if not 0 &lt;= channel &lt;= 7:
raise ValueError("Channel must be 0-7")
i2c_locked(i2c, i2c.writeto, TCA_ADDR, bytes([1 << channel]))
i2c_locked(i2c, i2c.writeto, TCA_ADDR, bytes([1 &lt;&lt; channel]))
</code></pre>
@ -605,7 +636,7 @@ def select_channel(i2c, channel):
<!-- Step 3 -->
<div class="prose">
<h2>Step 3: code.py</h2>
<h2>Step 3: main.py</h2>
<p>So in our main code we just import the muxer module, and make sure we switch to the correct
channel before sending any messages.</p>
</br>
@ -614,7 +645,7 @@ def select_channel(i2c, channel):
</div>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
# code.py
# main.py
import busio
import time
@ -683,51 +714,47 @@ while True:
<div class="prose">
<h2>Step 2: Coding</h2>
<p>The code for the OLED is a little more complicated that what we want to code for ourselves, so
we'll download a library and place it in out CIRCUITPY/lib folder.</p>
we'll upload this file to our device, or copy->paste the contents into a new file called ssd1306.py.</p>
</br>
<p><a href="files/adafruit_ssd1306.mpy">adafruit_ssd1306.mpy</a></p>
<p><a href="files/adafruit_framebuf.py">adafruit_framebuf.py</a></p>
<p><a href="files/ssd1306.py">ssd1306.py</a></p>
</br>
<p>We initialize the display with <code>display = adafruit_ssd1306.SSD1306_I2C(128, 32, i2c)</code>.
<p>We initialize the display with <code>disp = ssd1306.SSD1306_I2C(i2c)</code>.
</p>
</br>
<p>We colour the entire screen either black (off) or blue/white (on) with
<code>display.fill(0)</code> for off, or 1 for on.
<code>disp.fill(0)</code> for off, or 1 for on.
</p>
</br>
<p>We write text with <code>display.text(text, x, y, color)</code>.</p>
<p>We write text with <code>disp.text(text, x, y, color)</code>.</p>
</br>
<p>Finally, before anythin will actually appear on the screen, we send it using
<code>display.show()</code>.
<code>disp.show()</code>.
</p>
</div>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
import board
from machine import Pin, I2C
import time
import busio
import adafruit_ssd1306
import ssd1306
i2c = busio.I2C(scl=board.GP1, sda=board.GP0, frequency=1_000_000)
display = adafruit_ssd1306.SSD1306_I2C(128, 32, i2c)
i2c = I2C(0, scl=Pin(1), sda=Pin(0))
disp = ssd1306.SSD1306_I2C(i2c)
display.fill(0) # Fill the screen with BLACK
disp.fill(0) # Fill the screen with BLACK
# Print Hello world at the top left in COLOR
display.text("Hello World", 0, 0, 1)
display.show() # Send the update to the screen
disp.text("Hello World", 0, 0, 1)
disp.show() # Send the update to the screen
time.sleep(2)
display.fill(1)# Fille the screen with COLOR
display.show() # Send the update to the screen
disp.fill(1)# Fille the screen with COLOR
disp.show() # Send the update to the screen
time.sleep(2)
# Print Hello world at x:10, y:20 in BLACK
display.text("Hello World", 10, 20, 0)
display.show() # Send the update to the screen
disp.text("Hello World", 10, 20, 0)
disp.show() # Send the update to the screen
</code></pre>
@ -748,35 +775,29 @@ display.show() # Send the update to the screen
</div>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
import board
from machine import Pin, I2C
import time
import busio
import adafruit_ssd1306
import ssd1306
import color
import muxer
i2c = busio.I2C(scl=board.GP1, sda=board.GP0, frequency=1_000_000)
display = adafruit_ssd1306.SSD1306_I2C(128, 32, i2c)
i2c = I2C(0, scl=Pin(1), sda=Pin(0)) # Initialize the first I2C bus
i2c2 = I2C(1, scl=Pin(3), sda=Pin(2)) # Initialize the second I2C bus
disp = ssd1306.SSD1306_I2C(i2c)
# initialize two colour sensors
muxer.select_channel(i2c, 0)
color.init_sensor(i2c)
muxer.select_channel(i2c, 1)
color.init_sensor(i2c)
lc = color.Color(i2c2)
rc = color.Color(i2c)
while True:
# Read the colour channel from both colour sensors
muxer.select_channel(i2c, 0)
value0 = color.read_rgbc(i2c)[3]
muxer.select_channel(i2c, 1)
value1 = color.read_rgbc(i2c)[3]
left_color = lc.light()
right_color = rc.light()
# Print the results on the display
display.fill(0)
display.text("L: " + str(value0), 0, 0, 1)
display.text("R: " + str(value1), 0, 10, 1)
display.show()
disp.fill(0)
disp.text("L: " + str(left_color), 0, 0, 1)
disp.text("R: " + str(right_color), 0, 10, 1)
disp.show()
time.sleep(0.1)
</code></pre>
</div>
@ -816,16 +837,13 @@ while True:
<p>Once again we'll be using a library to handle all the bits and bytes under the hood, so we only
have to worry about setting colours.</p>
</br>
<p><a href="files/neopixel.py">neopixel.py</a></p>
</br>
<p>We only need to initialize the pixel with
<code>pixel = neopixel.NeoPixel(board.GP29, 1, brightness=0.2)</code>.
<code>pixel = neopixel.NeoPixel(Pin(16), 1)</code>.
</p>
<p>The "1" is the number of pixels we have, and we CAN set the brightness up to 1.0 but it's quite
bright.</p>
<p>The Pin is the RP2040 pin that the LED is connected to.The "1" is the number of pixels we have.</p>
</br>
<p>Then we just need to tell the pixel what colour to be, we talk to
<code>pixel[0] = (red,green,blue)</code> because
<code>pixel[0] = (green,red,blue)</code> because
it's the only one we have. The numbers for each colour go from minimum 0, to maximum 255.
</p>
@ -833,57 +851,30 @@ while True:
</div>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
import board
from machine import Pin
import time
import neopixel
pixel = neopixel.NeoPixel(board.GP29, 1, brightness=0.2)
pixel = neopixel.NeoPixel(Pin(16), 1)
pixel[0] = (20, 0, 0)
pixel.write()
while True:
pixel[0] = (255, 0, 0) # Red
pixel[0] = (255, 0, 0) # Green
pixel.write()
time.sleep(1)
pixel[0] = (0, 255, 0) # Green
pixel[0] = (0, 255, 0) # Red
pixel.write()
time.sleep(1)
pixel[0] = (0, 0, 255) # Blue
pixel.write()
time.sleep(1)
</code></pre>
</div>
<!-- Step 3 -->
<div class="prose">
<h2>Step 3: Make some pretty effects</h2>
<p>This example has three loops, each one fades from one primary colour to the next.</p>
</br>
<p>We increase one LEDs brightness by assigning it <code>i</code>, which counts from 0-255</p>
</br>
<p>We decrease another LEDs brightness by making it <code>255-i</code> so it begins at max, and
counts
down to zero as i becomes higher.</p>
</div>
<div>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
import board
import time
import neopixel
pixel = neopixel.NeoPixel(board.GP29, 1, brightness=0.2)
while True:
# Fade Red->Green
for i in range(256):
pixel[0] = (255-i, i, 0)
# Fade Green->Blue
for i in range(256):
pixel[0] = (0, 255-i, i)
# Fade Blue->Red
for i in range(256):
pixel[0] = (i, 0, 255-i)
</code></pre>
</div>
</section>
@ -959,9 +950,12 @@ class Sonar:
# Calculate duration
duration = time.ticks_diff(end, start)
# Convert to distance (speed of sound ~343 m/s)
distance = (duration / 2) * 0.0343
return int(distance)
# Convert to distance in millimeters
# Speed of sound ~343 m/s = 0.343 mm/µs
distance_mm = (duration / 2) * 0.343
return int(distance_mm)
</code></pre>
</div>
@ -983,8 +977,8 @@ sonar = sonar.Sonar(trigger_pin=26, echo_pin=28)
while True:
dist = sonar.distance()
print("Distance:", dist, "cm")
time.sleep(1)
print("Distance:", dist, "mm")
time.sleep(0.1)
</code></pre>
</div>
@ -1053,7 +1047,7 @@ class ThumbInput:
return None
def _map_thumbstick(self, x, min_val, mid_val, max_val):
if x < mid_val:
if x &lt; mid_val:
return (x - mid_val) / (mid_val - min_val) * 100
else:
return (x - mid_val) / (max_val - mid_val) * 100
@ -1190,7 +1184,8 @@ print(filtered)
<div class="prose">
<h2>Step 4: Take the median</h2>
<p>That's better, but those large peaks are still throwing our average off quite a bit. We can improve this by taking the MEDIAN of the buffer rather than the average.
<p>That's better, but those large peaks are still throwing our average off quite a bit. We can
improve this by taking the MEDIAN of the buffer rather than the average.
</p>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
def median_filter(values):
@ -1213,11 +1208,12 @@ print(filtered)
<div class="prose">
<h2>Step 5: Fine tuning</h2>
<p>Before moving on, play with the buffer size to see how it effects the results AND the responsiveness to changes.</p>
<p>Before moving on, play with the buffer size to see how it effects the results AND the
responsiveness to changes.</p>
<p>Try and find a good balance with the time.sleep() value as well.</p>
</div>
</div>
</section>
@ -1284,7 +1280,7 @@ class ThumbInput:
return None
def _map_thumbstick(self, x, min_val, mid_val, max_val):
if x < mid_val:
if x &lt; mid_val:
return (x - mid_val) / (mid_val - min_val) * 100
else:
return (x - mid_val) / (max_val - mid_val) * 100
@ -1442,7 +1438,7 @@ class PIDController:
</code></pre>
</br>
<pre class="bg-gray-100 p-4 rounded shadow text-sm"><code class="language-python">
# code.py
# main.py
import pid