Tinkering workshop
Introduction on Adafruit Circuit Playground Express
Install CircuitPython
Install mu editor
Python is the fastest-growing programming language. And CircuitPython is based on Python language but designed to run on microcontroller boards.
CircuitPython is designed with education in mind.
It's easy to start learning how to program and you get immediate feedback from the board.
Before we start we all have to do this to set up:
1. Install or update CircuitPython!
https://learn.adafruit.com/adafruit-circuit-playground-express/circuitpython-quickstart
*1. Click the link below and download the latest UF2 file: https://circuitpython.org/board/circuitplayground_express/
*2. Plug your Circuit Playground Express into your computer via a (data)USB cable.
*3. Double-click the small Reset button in the middle of the CPX(short for circuit playground express). you will see all of the LEDs turn green. If they turn all red, check the USB cable, try another USB port, etc. (If double-clicking doesn't do it, try a single-click!)
*4. You will see a new disk drive appear called CPLAYBOOT Drag the adafruit-circuitpython-etc...uf2 file onto it.
*5. The CPLAYBOOT drive will disappear and a new disk drive will appear called CIRCUITPY
That's it! You're done :)
2. Installing Mu Editor
Download Mu from(if you are using computers from school, the Mu Editor is already installed)
The first time you start Mu, you will be prompted to select your 'mode' -
you can always change your mind later. For now please select CircuitPython!
Mu attempts to auto-detect your board, so please plug in your CircuitPython device and make sure it shows up as a CIRCUITPY drive before starting Mu
SAVE AS:
if you want to save the code.py file in different names as well as in different locations:
double click on the file name in Mu editor.
Indentation and commenting options
Python programs are Space holder Character Sensitive.
To indent the three lines, I selected them all and then pressed the Tab key.
To unindent, select some lines and press Shift-Tab. For commenting: select lines and press command(control)-k
3. Hello World (Blink in Circuitpython)
1# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries
2# SPDX-License-Identifier: MIT
3
4"""This is the "Hello, world!" of CircuitPython: Blinky! This example blinks the little red LED on
5and off!"""
6
7import time
8from adafruit_circuitplayground import cp
9
10while True:
11 cp.red_led = True
12 time.sleep(0.5)
13 cp.red_led = False
14 time.sleep(0.5)
4. Interacting to the Serial Console
The REPL
The other feature of the serial connection is the Read-Evaluate-Print-Loop, or REPL.
The REPL allows you to enter individual lines of code and have them run immediately.
It's really handy if you're running into trouble with a particular program and can't figure out why.
It's interactive so it's great for testing new ideas.
To use the REPL, you first need to be connected to the serial console.
Once that connection has been established, you'll want to press Ctrl + C.
If there is code running, it will stop and you'll see Press any key to enter the REPL. Use CTRL-D to reload.
Follow those instructions, and press any key on your keyboard.
https://learn.adafruit.com/adafruit-circuit-playground-express/the-repl
CircuitPython Made Easy
Libraries:
Libraries are codes other people have written for you. The libraries we will be using are included as part of the CircuitPython code, but you still must import them into your program. Other libraries, for many uses, must be downloaded and placed in a folder named lib on the CIRCUITPY drive.
CircuitPython Libraries already included in CPX, But if you are using CPB, (CPX = Circuit Playground Express, CPB = Circuit Playground Bluefruit)
you need to install CircuitPython Libraries by download the file and put them in the folder named lib on the CIRCUITPY drive.
we will useCircuitPython Made Easy libraries, a simple way to include the Circuit Playground functionality in our code.
more reference and examples:
https://learn.adafruit.com/circuitpython-made-easy-on-circuit-playground-express
Interaction with touch sensor and neopixel
During this workshop, we will learn how to design and create an interactive game that enhances communication,
expression, and collaboration in the current 1.5 social distance reality.
we will focus on sending “touch signal” to each other without physical contact,
but in the forms of lights, color and sound.
1.Neopixel smiley face
A Smiley Face😊
from adafruit_circuitplayground import cp
# The NeoPixels are super-bright. Change the global brightness.
cp.pixels.brightness = 0.3
while True:
# The smiley's eyes
cp.pixels[1] = (255, 0, 0)
cp.pixels[3] = (255, 0, 0)
# The smiley's mouth
cp.pixels[5] = (255, 0, 255)
cp.pixels[6] = (255, 0, 255)
cp.pixels[7] = (255, 0, 255)
cp.pixels[8] = (255, 0, 255)
cp.pixels[9] = (255, 0, 255)
Let's blink a smiley face by using time.sleep
1from adafruit_circuitplayground import cp
2
3# The NeoPixels are super-bright. Change the global brightness.
4cp.pixels.brightness = 0.3
5
6import time
7
8while True:
9 time.sleep(1)
10 # The smiley's eyes
11 cp.pixels[1] = (255, 0, 0)
12 cp.pixels[3] = (255, 0, 0)
13
14 # The smiley's mouth
15 cp.pixels[5] = (255, 0, 255)
16 cp.pixels[6] = (255, 0, 255)
17 cp.pixels[7] = (255, 0, 255)
18 cp.pixels[8] = (255, 0, 255)
19 cp.pixels[9] = (255, 0, 255)
20 time.sleep(1)
21
22 # The smiley's eyes
23 cp.pixels[1] = (0, 0, 0)
24 cp.pixels[3] = (0, 0, 0)
25
26 # The smiley's mouth
27 cp.pixels[5] = (0, 0, 0)
28 cp.pixels[6] = (0, 0, 0)
29 cp.pixels[7] = (0, 0, 0)
30 cp.pixels[8] = (0, 0, 0)
31 cp.pixels[9] = (0, 0, 0)
hmm... now the code seems to be too long
let's Shorten the code by implementing variables, "for" loops
1import time
2from adafruit_circuitplayground import cp
3#neoPixel pins for the smiley face
4pixels_pin=[1, 3, 5, 6, 7, 8, 9,10]
5# The NeoPixels are super-bright. Change the global brightness.
6cp.pixels.brightness = 0.1
7light_colour=(105,0,105)
8OFF=(0,0,0)
9
10while True:
11 for i in range (7):
12 cp.pixels[pixels_pin[i]]=light_colour
13 time.sleep(1)
14 for i in range (7):
15 cp.pixels[pixels_pin[i]]=OFF
16 time.sleep(1)
much better!!! now if you add a time.sleep(0.5) in the for loop you will see a fading animation of the smiley face.
2.Touch sense as trigger
there are in total 7 touch pins on CPX. let's try to use the touch sensor to trigger the smiley face.
if we touch pin A4, The smiley face will appear if not the smiley face will disappear.
1import time
2from adafruit_circuitplayground import cp
3#neoPixel pins for the smiley face
4pixels_pin=[1, 3, 5, 6, 7, 8, 9,10]
5# The NeoPixels are super-bright. Change the global brightness.
6cp.pixels.brightness = 0.1
7light_colour=(105,0,105)
8OFF=(0,0,0)
9
10while True:
11 if cp.touch_A4:
12 for i in range (7):
13 cp.pixels[pixels_pin[i]]=light_colour
14 time.sleep(.1)
15 print("A4-touched!")
16 else:
17 for i in range (7):
18 cp.pixels[pixels_pin[i]]=OFF
19 time.sleep(.1)
3.Touch piano keyboard
1import time
2from adafruit_circuitplayground import cp
3#neoPixel pins for the smiley face
4pixels_pin=[1, 3, 5, 6, 7, 8, 9,10]
5
6playtime=0.2
7# NOTE C4-B4
8c4=262
9d4=294
10e4=330
11f4=349
12g4=392
13a4=440
14b4=494
15
16while True:
17 if cp.touch_A1:
18 cp.play_tone(c4, playtime)
19 print("A1-touched!")
20 if cp.touch_A2:
21 cp.play_tone(d4, playtime)
22 print("A2-touched!")
23 if cp.touch_A3:
24 cp.play_tone(e4, playtime)
25 print("A3-touched!")
26 if cp.touch_A4:
27 cp.play_tone(f4, playtime)
28 print("A4-touched!")
29 if cp.touch_A5:
30 cp.play_tone(g4, playtime)
31 print("A5-touched!")
32 if cp.touch_A6:
33 cp.play_tone(a4, playtime)
34 print("A6-touched!")
35 if cp.touch_A7:
36 cp.play_tone(b4, playtime)
37 print("A7-touched!")
3.Play audio file
here some audio files you can download and copy to the circuit playground express.
Dip: http://interactionstation.wdka.hro.nl/mediawiki/images/6/61/Dip.wav
Rise: http://interactionstation.wdka.hro.nl/mediawiki/images/2/2b/Rise.wav
Explosion: http://interactionstation.wdka.hro.nl/mediawiki/images/f/f8/Explosion.wav
Kiss.wav: http://interactionstation.wdka.hro.nl/mediawiki/images/d/df/Kiss.wav
Happy-ringtone: http://interactionstation.wdka.hro.nl/mediawiki/images/9/9b/Happy-ringtone.wav
Wrong-buzzer: http://interactionstation.wdka.hro.nl/mediawiki/images/6/61/Wrong-buzzer.wav
Yelling-yeah: http://interactionstation.wdka.hro.nl/mediawiki/images/9/95/Yelling-yeah.wav
Jazz-piano: http://interactionstation.wdka.hro.nl/mediawiki/images/a/a9/Jazz-piano.wav
1import time
2from adafruit_circuitplayground import cp
3#neoPixel pins for the smiley face
4pixels_pin=[1, 3, 5, 6, 7, 8, 9,10]
5
6# The NeoPixels are super-bright. Change the global brightness.
7cp.pixels.brightness = 0.1
8colour01=(105,0,105)
9colour02=(0,100,105)
10OFF=(0,0,0)
11
12while True:
13 if cp.touch_A4:
14 for i in range (7):
15 cp.pixels[pixels_pin[i]]=colour01
16 time.sleep(0.03)
17 print("A4-touched!")
18 cp.play_file("yelling-yeah.wav")
19 else:
20 for i in range (7):
21 cp.pixels[pixels_pin[i]]=OFF
22 time.sleep(0.03)
23 if cp.touch_A3:
24 for i in range (7):
25 cp.pixels[pixels_pin[i]]=colour02
26 time.sleep(0.03)
27 print("A3-touched!")
28
29 cp.play_file("jazz-piano.wav")
30 else:
31 for i in range (7):
32 cp.pixels[pixels_pin[i]]=OFF
33 time.sleep(0.03)
4.Drum Machine
https://learn.adafruit.com/adafruit-circuit-playground-express/playground-drum-machine
copy the drum samples there:
[samples]
1# Circuit Playground 808 Drum machine
2import time
3import board
4import touchio
5import digitalio
6
7try:
8 from audiocore import WaveFile
9except ImportError:
10 from audioio import WaveFile
11
12try:
13 from audioio import AudioOut
14except ImportError:
15 try:
16 from audiopwmio import PWMAudioOut as AudioOut
17 except ImportError:
18 pass # not always supported by every board!
19
20bpm = 120 # Beats per minute, change this to suit your tempo
21
22# Enable the speaker
23speaker_enable = digitalio.DigitalInOut(board.SPEAKER_ENABLE)
24speaker_enable.direction = digitalio.Direction.OUTPUT
25speaker_enable.value = True
26
27# Make the input capacitive touchpads
28capPins = (board.A1, board.A2, board.A3, board.A4, board.A5,
29 board.A6, board.TX)
30
31touchPad = []
32for i in range(7):
33 touchPad.append(touchio.TouchIn(capPins[i]))
34
35# The seven files assigned to the touchpads
36audiofiles = ["bd_tek.wav", "elec_hi_snare.wav", "elec_cymbal.wav",
37 "elec_blip2.wav", "bd_zome.wav", "bass_hit_c.wav",
38 "drum_cowbell.wav"]
39
40audio = AudioOut(board.SPEAKER)
41
42
43def play_file(filename):
44 print("playing file " + filename)
45 file = open(filename, "rb")
46 wave = WaveFile(file)
47 audio.play(wave)
48 time.sleep(bpm / 960) # Sixteenth note delay
49
50
51while True:
52 for i in range(7):
53 if touchPad[i].value:
54 play_file(audiofiles[i])
connect to a proper speaker:
we can use A0 and GND as audio output and connect it to a proper speaker.
you can use M3 bolts and nuts to fix the electrical wire on the circuit playground express.
infrared tagging game:
1import board
2from adafruit_circuitplayground import cp
3import time
4import pulseio
5import array
6import sys
7
8# change into your own color by changing the rgb value
9myID_color = (0, 55, 50)
10OFF = (0, 0, 0)
11color_got_hit = (255, 0, 0)
12color_got_saved = (100, 0, 100)
13Neo_smiley_face = [4, 5, 1, 0, 8, 9]
14full_led = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
15counter = 0
16lifes = 10-counter
17
18# Initializes NeoPixel ring
19cp.pixels.brightness = 0.2
20# my id color
21cp.pixels.fill(myID_color)
22
23
24# Create IR input, maximum of 59 bits.
25pulseIn = pulseio.PulseIn(board.IR_RX, maxlen=59, idle_state=True)
26# Clears any artifacts
27pulseIn.clear()
28pulseIn.resume()
29
30# Creates IR output pulse
31pwm = pulseio.PWMOut(board.IR_TX, frequency=38000, duty_cycle=2 ** 15)
32pulse = pulseio.PulseOut(pwm)
33
34# Array for button A pulse, this is the pulse output when the button is pressed
35# Inputs are compared against this same array
36# array.array('H', [x]) must be used for IR pulse arrays when using pulseio
37# indented to multiple lines so its easier to see
38pulse_A = array.array('H', [1000, 3800, 65000, 950, 300, 200, 300, 1000, 350, 175,
39 275, 215, 275, 250, 275, 215, 275, 225, 275, 215, 275, 1000, 300, 225, 275,
40 950, 300, 950, 300, 1000, 300, 950, 300, 250, 275, 700, 300, 950, 300, 450,
41 300, 475, 300, 215, 275, 725, 300, 950, 300, 200, 300, 715, 325, 900, 315,
42 425, 315, 1000, 65000])
43pulse_B = array.array('H', [1000, 3800, 65000, 960, 300, 200, 300, 950, 350, 190,
44 215, 245, 300, 225, 275, 225, 275, 215, 275, 200, 300, 700, 300, 200, 300,
45 700, 300, 1000, 315, 675, 300, 1000, 300, 200, 300, 700, 300, 950, 300,
46 950, 300, 700, 300, 700, 300, 450, 300, 475, 275, 715, 300, 225, 275, 450,
47 300, 450, 300, 1000, 65000])
48
49# Fuzzy pulse comparison function. Fuzzyness is % error
50def fuzzy_pulse_compare(pulse1, pulse2, fuzzyness=0.5):
51 if len(pulse1) != len(pulse2):
52 return False
53 for i in range(len(pulse1)):
54 threshold = int(pulse1[i] * fuzzyness)
55 if abs(pulse1[i] - pulse2[i]) > threshold:
56 return False
57 return True
58
59
60# serial print once when activated
61print('IR Activated!')
62
63while True:
64 # when A3 or A4 is Touched, send IR pulse
65 # detection is paused then cleared and resumed after a short pause
66 # this prevents reflected detection of own IR
67 while cp.touch_A3:
68 pulseIn.pause() # pauses IR detection
69 pulse.send(pulse_A) # sends IR pulse
70 time.sleep(.2) # wait so pulses dont run together
71 pulseIn.clear() # clear any detected pulses to remove partial artifacts
72 pulseIn.resume() # resumes IR detection
73 while cp.touch_A4:
74 pulseIn.pause()
75 pulse.send(pulse_B)
76 time.sleep(.2)
77 pulseIn.clear()
78 pulseIn.resume()
79# Wait for a pulse to be detected of desired length
80 # our array is 59 bytes so anything shorter ignore
81 while len(pulseIn) >= 59:
82 pulseIn.pause()
83# converts pulseIn raw data into useable array
84 detected = array.array('H', [pulseIn[x] for x in range(len(pulseIn))])
85# print(len(pulseIn))
86# print(detected)
87
88 # Got a pulse, now compare against stored pulse_A and pulse_B
89 if fuzzy_pulse_compare(pulse_A, detected):
90 print('Received A3 control A!')
91 t_end = time.monotonic() + 0.8 # saves time 2 seconds in the future
92 while time.monotonic() < t_end:
93 cp.pixels.fill(OFF)
94 for x in range(6):
95 cp.pixels[Neo_smiley_face[x]] = (color_got_saved)
96 cp.play_file("yelling-yeah.wav")
97 time.sleep(0.2)
98
99 if counter < 10 and counter > 0:
100 counter = counter-1
101 lifes = 10-counter
102 cp.pixels.fill(OFF)
103
104 else:
105 for i in range(lifes):
106 cp.pixels[full_led[i]] = myID_color
107 pulseIn.clear()
108 pulseIn.resume()
109
110 if fuzzy_pulse_compare(pulse_B, detected):
111 print('Received A4 control B !')
112 t_end = time.monotonic() + 0.8
113 while time.monotonic() < t_end:
114 print(counter)
115 print(lifes)
116 cp.pixels.fill(OFF)
117 cp.pixels.fill(color_got_hit)
118
119 cp.play_file("failure.wav")
120 time.sleep(0.2)
121 counter = counter+1
122 lifes = 10-counter
123 if lifes < 1:
124 sys.exit()
125 cp.pixels.fill(OFF)
126 for i in range(lifes):
127 cp.pixels[full_led[i]] = myID_color
128
129 else:
130 for i in range(lifes):
131 cp.pixels[full_led[i]] = myID_color
132 pulseIn.clear()
133 pulseIn.resume()
134
135 time.sleep(.1)
136 pulseIn.clear()
137 pulseIn.resume()