One of my old ideas, never made or tested.
I saw a post on Reddit with this question, I decided to post a little drawing using my idea.
Center of below picture shows pages (the lines), with coppertape going front to back and connect to following page
Inductive copper tape
New version of :
New schematic using ESPHOME and has reset button (pressing the lid).
(Resets the LED when you’ve put the trash at the street curb.)
Above, a simplified version. I’m using 4 ws2812 leds now.
ESPHOME code:
esphome:
name: afvalwemos
friendly_name: AfvalWemos
on_boot:
priority: 800
then:
- delay: 1s
- light.turn_off: main_leds
esp8266:
board: d1_mini
# Enable logging
logger:
# Enable Home Assistant API
api:
encryption:
key: "bT76oR8vOxxxxxxxxxxxxxxxxxxxxxxxxQbyjY6M="
ota:
- platform: esphome
password: "c1dbxxxxxxxxxxxxxxxxxxxxxxxxxx36e75"
wifi:
ssid: !secret wifi_ssid
password: !secret wifi_password
# Enable fallback hotspot (captive portal) in case wifi connection fails
ap:
ssid: "Afvalwemos Fallback Hotspot"
password: "vVxxxxxxxxxxxxxxaw"
captive_portal:
# LED strip definition
light:
- platform: neopixelbus
type: RGB
variant: WS2812
pin: D5
num_leds: 4
name: "All LEDs"
id: main_leds
restore_mode: ALWAYS_OFF # ensures all LEDs start off
# Individual LED partitions
- platform: partition
name: "LED 1"
segments:
- id: main_leds
from: 0
to: 0
- platform: partition
name: "LED 2"
segments:
- id: main_leds
from: 1
to: 1
- platform: partition
name: "LED 3"
segments:
- id: main_leds
from: 2
to: 2
- platform: partition
name: "LED 4"
segments:
- id: main_leds
from: 3
to: 3
# Physical button on D6 to turn off all LEDs
binary_sensor:
- platform: gpio
pin:
number: D6
mode: INPUT_PULLUP
inverted: True
name: "All Off Button"
on_press:
- logger.log: "Button pressed — turning all LEDs OFF"
- light.turn_off: main_leds
Home Assistant automation:
alias: Afvalwijzer Plastic
description: Afvalwijzer leds
triggers:
- at: "18:00:00"
trigger: time
conditions:
- condition: template
value_template: >
{% set raw = states('sensor.gad_pmd') %} {% if raw not in ['unknown',
'unavailable', 'none', ''] %}
{% set clean = raw.replace('Tomorrow, ', '').replace('Today, ', '').strip() %}
{% set parts = clean.split(', ') %}
{% set date_part = parts[-1] if parts|length > 1 else clean %}
{% set pmd_date = strptime(date_part, '%d-%m-%Y').date() %}
{% set tomorrow = (now().date() + timedelta(days=1)) %}
{{ pmd_date == tomorrow }}
{% else %}
false
{% endif %}
actions:
- action: light.turn_on
target:
entity_id: light.afvalwemos_led_3
data:
rgb_color:
- 236
- 199
- 14
mode: single
Remember those expensive touch lights you can buy?
This is a less than 5 euro version.
Warning : Some tricks I used
TTP223 sensors are only a few cents!
And react even without touching (< 5mm)
So, you can build this in a case or behind fabric!
NOTE: If you are using an ESP32 you can configure a pin as touch!!!
So no TTP223 needed.
But ESP32 are more expensive as Wemos mini.
Code:
#define TOUCH_PIN D2 // My video has D7
#define LED_PIN D6
#define FAKE_GND D5
// Brightness steps (0 = off, 255 = full bright)
int brightnessLevels[] = {0, 25, 125, 255};
int currentLevel = 0;
bool lastTouchState = LOW;
void setup() {
pinMode(TOUCH_PIN, INPUT);
pinMode(LED_PIN, OUTPUT);
pinMode(FAKE_GND, OUTPUT);
digitalWrite(FAKE_GND, LOW);
analogWrite(LED_PIN, brightnessLevels[currentLevel]); // start OFF
}
void loop() {
bool touchState = digitalRead(TOUCH_PIN);
if (touchState == HIGH && lastTouchState == LOW) {
// Advance brightness step
currentLevel = (currentLevel + 1) % 4; // 0-3 steps
int pwmValue = brightnessLevels[currentLevel];
analogWrite(LED_PIN, pwmValue);
}
lastTouchState = touchState;
}
Dim levels less obvious on recording, but you can change the levels in the code!
While I made this for my Commodore C64, it is applicable for many things.
It started with some cheap displays from Ali, and some leftover Wemos D1 from my Pressure Lab project.
I Started measuring the audio output from sound devices and from my C64.
I soon discovered that I needed some way to get the offset and amplification correct for the analogue input of a Wemos. (0-3v3)
So a little op-amp circuit was born, but not without some struggles.
I forgot many things about amplifiers. It was one of the first school books I got rid of. (Sorry mister Rafaela)
After searching the internet and posting a question on Reddit I ended up with the following.
R1 and R2 are 100M. The potentiometer P1 allows me to set the offset.
R3 is 1M
C1 is 100nF to decouple the audio signal from the RCA.
R4 is 47K and C2 is 330nF (thanks tycho205)
Cimportant=1/(2πfR2)
where f is the lowest frequency of interest. In this case Cimportant should be about 330nF
LM324 is a quad amplifier, leftover from another project.
Note, the SINGLE RAIL power.
P2 potentiometer is 2M (leftover) and gives me a variable amplifying opportunity.
A = Audio input
B = Setting the offset with P1
C = Setting the amplification
The displays are 3 Wemos controllers with a cheap I2C display.
These are just fast enough to do FFT.
Analogue in is the output from the OP-amp offsetter ..
CODE
Needs cleaning up, and a better stabilize routine.
A while ago I made a little notify thingy using an LCD display, LED, button and a buzzer.
Some friends of mine made one also, and today I was talking to a new guy.
I could not find this project on my site .. again .. so I’ll post it now.
Some things it does right now
Doorbell pressed: Led starts blinking, backlight LCD enabled, text displayed on LCD, Buzzer sounds (or plays a RTTTL ringtone)
LCD backlight on and buzzer beep until acknowledge button pressed.
Heating for brewing: temperature on display, led on when temperature reached. Press acknowledge to start timer.
….. etc
CODE:
esphome:
name: lcdalarm
friendly_name: LCDAlarm
on_boot:
priority: -100.0
then:
- lambda: 'id(lcddisplay).no_backlight();'
esp8266:
board: d1_mini
# Enable logging
logger:
# Enable Home Assistant API
api:
encryption:
key: "OOpDzMu0VvfWAnJXXXXXXXXXXXXXXXXXXXXXXXXKNDa74OJ1Cc="
ota:
- platform: esphome
password: "627992017XXXXXXXXXXXXXXX738c2a3"
wifi:
ssid: !secret wifi_ssid
password: !secret wifi_password
# Enable fallback hotspot (captive portal) in case wifi connection fails
ap:
ssid: "Lcdalarm Fallback Hotspot"
password: "z9dZXXXXXXXX7a"
captive_portal:
web_server:
port: 80
i2c:
sda: D2
scl: D1
scan: true
frequency: 400kHz
light:
- platform: binary
name: "Status LED"
output: light_output
icon: "mdi:led-on"
id: led
binary_sensor:
- platform: gpio
pin:
inverted: true
number: D5
mode:
input: true
pullup: true
name: "LCD Button"
text_sensor:
# Create text input helper in homeassistant and enter id below
- platform: homeassistant
entity_id: input_text.lcd_display_text
id: lcd_display_text
- platform: wifi_info
ip_address:
id: ip_address
name: IP address
mac_address:
id: mac_address
name: Mac address
ssid:
id: connected_ssid
name: Network SSID
bssid:
id: connected_
name: Network Mac
sensor:
- platform: wifi_signal
id: wifisignal
name: wifi-signal
update_interval: 300s
globals:
- id: backlight_on
type: bool
initial_value: 'false'
- id: flash_beep_on
type: bool
initial_value: 'false'
switch:
- platform: template
name: "LCD Backlight"
id: backlight
restore_mode: RESTORE_DEFAULT_OFF
turn_on_action:
- globals.set:
id: backlight_on
value: 'true'
- globals.set:
id: flash_beep_on
value: 'false'
- lambda: |-
id(lcddisplay).backlight();
- delay: 5s
turn_off_action:
- globals.set:
id: backlight_on
value: 'false'
- lambda: |-
id(lcddisplay).no_backlight();
lambda: |-
return id(backlight_on);
- platform: template
name: "Flash and Beep"
id: flash_beep
restore_mode: RESTORE_DEFAULT_OFF
turn_on_action:
- globals.set:
id: flash_beep_on
value: 'true'
- globals.set:
id: backlight_on
value: 'false'
- lambda: |-
id(lcddisplay).backlight();
- lambda: |-
id(buzzer).turn_on();
- delay: 0.75s
- lambda: |-
id(lcddisplay).no_backlight();
- lambda: |-
id(buzzer).turn_off();
- delay: 0.75s
- lambda: |-
id(lcddisplay).backlight();
- lambda: |-
id(buzzer).turn_on();
- delay: 0.75s
- lambda: |-
id(lcddisplay).no_backlight();
- lambda: |-
id(buzzer).turn_off();
- delay: 0.75s
- lambda: |-
id(lcddisplay).backlight();
- lambda: |-
id(buzzer).turn_on();
- delay: 0.75s
- lambda: |-
id(lcddisplay).no_backlight();
- lambda: |-
id(buzzer).turn_off();
- delay: 0.75s
- lambda: |-
id(lcddisplay).backlight();
turn_off_action:
- globals.set:
id: flash_beep_on
value: 'false'
- lambda: |-
id(lcddisplay).no_backlight();
- lambda: |-
id(buzzer).turn_off();
lambda: |-
return id(flash_beep_on);
- platform: restart
name: "Restart ESPhome"
output:
- platform: gpio
pin: D3
id: buzzer
- platform: gpio
pin: D6
id: light_output
display:
- platform: lcd_pcf8574
id: lcddisplay
dimensions: 16x2
address: 0x27
lambda: |-
if(id(wifisignal).has_state()) {
if (id(lcd_display_text).state != "") {
it.print(0, 0, id(lcd_display_text).state.c_str());
}
} else {
it.print(" ESPhome booting... ");
}
CODE: RTTTL (Use passive buzzer!!!!)
esphome:
name: lablcd
friendly_name: LabLCD
esp8266:
board: d1_mini
# Enable logging
logger:
# Enable Home Assistant API
api:
encryption:
key: "ga17mNCtxdiXXXXXXXXXXXXXXXXXXXXX70a5W0VPZR51Q="
actions:
- action: rtttl_play
variables:
song_str: string
then:
- rtttl.play:
rtttl: !lambda 'return song_str;'
ota:
- platform: esphome
password: "84013b9XXXXXXXXXXXXXXX5401039f7c"
wifi:
ssid: !secret wifi_ssid
password: !secret wifi_password
# Enable fallback hotspot (captive portal) in case wifi connection fails
ap:
ssid: "Lablcd Fallback Hotspot"
password: "nnzXXXXXXXXXXXXXXXXXXXCb"
rtttl:
output: rtttl_out
on_finished_playback:
- logger.log: 'Song ended!'
captive_portal:
i2c:
sda: D2
scl: D1
scan: true
frequency: 400kHz
light:
- platform: status_led
name: "Status LED"
icon: "mdi:led-on"
pin:
number: D5
inverted: true
binary_sensor:
- platform: gpio
name: "Push Button"
pin:
number: D4
inverted: true
mode:
input: true
pullup: true
on_press:
- homeassistant.service:
service: homeassistant.toggle
data:
entity_id: input_boolean.esphome_notification_lcdlab_push_button
text_sensor:
# Create text input helper in homeassistant and enter id below
- platform: homeassistant
entity_id: input_text.esphome_notification_lcdlcd_display_text
id: lcd_display_text
- platform: wifi_info
ip_address:
id: ip_address
name: IP address
mac_address:
id: mac_address
name: Mac address
ssid:
id: connected_ssid
name: Network SSID
bssid:
id: connected_
name: Network Mac
sensor:
- platform: wifi_signal
id: wifisignal
name: wifi-signal
update_interval: 300s
globals:
- id: backlight_on
type: bool
initial_value: 'false'
- id: flash_beep_on
type: bool
initial_value: 'false'
switch:
- platform: template
name: "LCD Backlight Lab"
id: backlight
restore_mode: RESTORE_DEFAULT_OFF
turn_on_action:
- globals.set:
id: backlight_on
value: 'true'
- globals.set:
id: flash_beep_on
value: 'false'
- lambda: |-
id(lcddisplay).backlight();
turn_off_action:
- globals.set:
id: backlight_on
value: 'false'
- lambda: |-
id(lcddisplay).no_backlight();
lambda: |-
return id(backlight_on);
- platform: restart
name: "Restart ESPhome"
output:
- platform: esp8266_pwm
pin: D8
id: rtttl_out
display:
- platform: lcd_pcf8574
id: lcddisplay
dimensions: 16x2
address: 0x27
lambda: |-
if(id(wifisignal).has_state()) {
if (id(lcd_display_text).state != "") {
it.print(0, 0, id(lcd_display_text).state.c_str());
}
} else {
it.print(" ESPhome booting... ");
}
I bought a little audio shield for the Teensy 4.0.
Using the designer at : https://www.pjrc.com/teensy/gui/
And some Arduino code I made a little midi player.
Melody is being sent with PureData over Midi-USB
Config designer for teensy
Very nice toy, lots to experiment with.
I was planning to make a RSS reader using this display, but I came across a weather display project I wanted to check out.
(So I probably end up buying another one)
There are many questions and issues around this project using the S3.
So here is my solution.
Install vscode
Goto plugins and install platformio
git clone https://github.com/Xinyuan-LilyGO/LilyGo-EPD-4-7-OWM-Weather-Display.git
Warning this is NOT the branch you want to use
git checkout web
(git pull)
open directory in code
open platformio.ini and change line 13
default_envs = T5_4_7Inc_Plus_V2
(If needed add upload_port = /dev/tty**** at the end)
Change INO file lines 144-146.
Comment serial out, else update won’t work using regular power or battery.
When saving this platformio.ini file, some downloading and installing should be popping up.
When issues occur about libraries see below.
Fill out
data>config.json
and owm_credentials.h to be sure.
(use owm_credentials information to fill config.json)
Next press the platformio icon
Fix for uploading:
Press and hold STR_IO0 button
Press REST button
Release STR_IO0 button
Libraries:
Press platformio icon, libaries and install ArduinoJson, Button2 and LilyGo-EPD47 (select your project while doing so!)
Note: Per default once per hour update, change if you want to.
Line 70 in the INO file
Build/Upload errors? .. Press clean to recompile using a clean state !
While I’ve used a Laptop with a ping script I made in the past, I needed something more portable.
So I build:
This way I can use both hands, hanging upside-down in a hard-to-reach place, without turning my head to a screen or my phone.
CODE (Below code is for D6)
#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <WiFiManager.h>
#include <ESP8266Ping.h>
ESP8266WebServer server(80);
String pingHost = "";
bool startPinging = false;
unsigned long lastPingTime = 0;
bool gpioState = false;
void setup() {
Serial.begin(115200);
pinMode(D6, OUTPUT);
// WiFiManager captive portal
WiFiManager wm;
if (!wm.autoConnect("ESP_SetupAP")) {
Serial.println("Failed to connect, restarting...");
ESP.restart();
}
Serial.println("WiFi connected. IP:");
Serial.println(WiFi.localIP());
// Web UI
server.on("/", HTTP_GET, []() {
String html = "<html><body><h2>ESP Continuous Ping</h2>"
"<form action='/start'>"
"Host/IP to ping: <input name='host' type='text'>"
"<input type='submit' value='Start Pinging'>"
"</form></body></html>";
server.send(200, "text/html", html);
});
server.on("/start", HTTP_GET, []() {
if (!server.hasArg("host")) {
server.send(400, "text/plain", "Missing 'host' parameter.");
return;
}
pingHost = server.arg("host");
startPinging = true;
server.send(200, "text/plain", "Started pinging " + pingHost);
});
server.begin();
}
void loop() {
server.handleClient();
if (startPinging && millis() - lastPingTime > 2000) {
lastPingTime = millis();
bool success = Ping.ping(pingHost.c_str(), 1);
if (success) {
gpioState = !gpioState;
digitalWrite(D6, HIGH);
delay(500);
digitalWrite(D6, LOW);
delay(500);
Serial.println("Ping success, toggled D6.");
} else {
Serial.println("Ping failed.");
digitalWrite(D6, LOW);
}
}
}
Further ideas
Or anything else. ( idea from a reddit post )
UPDATE: 20250523
Combining a GPS module, compass, a LED ring and some code, I want to make a little device which shows you the way to the nearest … something.
To make it completely standalone, I have to use a SIM module. (Same as I have used before) This POC will use my phone as hotspot.
The LED ring will show the direction to go.
Edit: Maybe not a LED ring but a little display.
As previously posted, I was playing with Overpass turbo.
Using an API, I can use code to query this.
Test code for my web server to query the data
import overpy
import math
api = overpy.Overpass()
# This location will be filled with data from GPS module on Arduino.
latitude = 52.2270745 # Center latitude (e.g. Berlin)
longitude = 5.177519 # Center longitude
box_size = 0.05 # Box size in degrees (about ~5 km)
south = latitude - box_size
north = latitude + box_size
west = longitude - box_size
east = longitude + box_size
def haversine(lat1, lon1, lat2, lon2):
R = 6371 # Earth radius in km
phi1 = math.radians(lat1)
phi2 = math.radians(lat2)
d_phi = math.radians(lat2 - lat1)
d_lambda = math.radians(lon2 - lon1)
a = math.sin(d_phi / 2)**2 + math.cos(phi1) * math.cos(phi2) * math.sin(d_lambda / 2)**2
c = 2 * math.atan2(math.sqrt(a), math.sqrt(1 - a))
return R * c # Distance in kilometers
# Calculate bearing in degrees (0-360)
def bearing(lat1, lon1, lat2, lon2):
phi1 = math.radians(lat1)
phi2 = math.radians(lat2)
delta_lon = math.radians(lon2 - lon1)
x = math.sin(delta_lon) * math.cos(phi2)
y = math.cos(phi1) * math.sin(phi2) - math.sin(phi1) * math.cos(phi2) * math.cos(delta_lon)
initial_bearing = math.atan2(x, y)
compass_bearing = (math.degrees(initial_bearing) + 360) % 360 # Normalize to 0–360
return compass_bearing
# Overpass QL query
query = f"""
[out:json];
node
["shop"="alcohol"]
({south}, {west}, {north}, {east});
out body;
>;
out skel qt;
"""
try:
result = api.query(query)
# Collect and sort places by distance
places = []
for node in result.nodes:
node_lat = float(node.lat)
node_lon = float(node.lon)
distance = haversine(latitude, longitude, node_lat, node_lon)
direction = bearing(latitude, longitude, node_lat, node_lon)
name = node.tags.get("name", "Unnamed")
places.append((distance, direction, name, node_lat, node_lon))
places.sort()
print(f"Found {len(places)} alcohol-related places sorted by distance:")
for dist, dir_deg, name, lat, lon in places:
print(f"- {name} at ({lat:.5f}, {lon:.5f}) — {dist:.2f} km, {dir_deg:.0f}°")
except Exception as e:
print(f"Error: {e}")
Output:
Found 10 alcohol-related places sorted by distance:
- The Skiff at (52.22583, 5.17860) — 0.16 km, 152°
- Onzewijnen at (52.22612, 5.17045) — 0.49 km, 258°
- Gall & Gall at (52.23244, 5.19204) — 1.15 km, 59°
- Gall & Gall at (52.21536, 5.16735) — 1.48 km, 208°
- Eric's Beer Craft at (52.21549, 5.16632) — 1.50 km, 211°
- Slijterij at (52.21082, 5.15692) — 2.29 km, 218°
- Gall & Gall at (52.21590, 5.14074) — 2.80 km, 244°
- Gall & Gall at (52.25422, 5.22705) — 4.53 km, 48°
- Gall & Gall at (52.26808, 5.18348) — 4.58 km, 5°
- Il DiVino at (52.27507, 5.16414) — 5.41 km, 350°
Example using Overpass Turbo to find breweries
Other ideas
UPDATE
Building the hardware : First design
Some test code
#include "SPI.h"
#include "Adafruit_GFX.h"
#include "Adafruit_GC9A01A.h"
// Overrule stuff
#define TFT_CS 18 // Chip select
#define TFT_DC 5 // Data/command mode
#define TFT_BL 4 // Backlight control
#define TFT_MOSI 12 // SPI Out AKA SDA
#define TFT_SCLK 13 // Clock out AKA SCL
#define TFT_MISO -1 // pin not used
#define TFT_RST 23 // Reset ################# IMPORTANT, won't work without!! Took me a hour!
// Need this changed from example also
Adafruit_GC9A01A tft(TFT_CS, TFT_DC,TFT_MOSI,TFT_SCLK,TFT_RST,TFT_MISO);
float angle = 0;
void setup() {
tft.begin();
tft.setRotation(0);
tft.fillScreen(GC9A01A_BLACK);
drawCompassFace();
}
void loop() {
drawNeedle(angle, GC9A01A_RED);
delay(1000);
drawNeedle(angle, GC9A01A_BLACK); // Erase previous needle
angle += 15;
if (angle >= 360) angle = 0;
tft.setCursor(60, 100);
tft.setTextColor(GC9A01A_WHITE); tft.setTextSize(2);
tft.println("230 Meters");
}
// Draw static compass face
void drawCompassFace() {
int cx = tft.width() / 2;
int cy = tft.height() / 2;
int radius = 100;
tft.drawCircle(cx, cy, radius, GC9A01A_WHITE);
tft.setTextColor(GC9A01A_WHITE);
tft.setTextSize(1);
tft.setCursor(cx - 3, cy - radius + 5); tft.print("N");
tft.setCursor(cx - 3, cy + radius - 10); tft.print("S");
tft.setCursor(cx - radius + 5, cy - 3); tft.print("W");
tft.setCursor(cx + radius - 10, cy - 3); tft.print("E");
}
// Draw compass needle
void drawNeedle(float angleDeg, uint16_t color) {
int cx = tft.width() / 2;
int cy = tft.height() / 2;
float angleRad = angleDeg * DEG_TO_RAD;
int x = cx + cos(angleRad) * 90;
int y = cy + sin(angleRad) * 90;
tft.drawLine(cx, cy, x, y, color);
}
Where is it, what device could it be?
Its SSID started with ESP. So I probably am the one responsible for its existence.
I’ve got a sh*tload of ESPs/NodeMCUs/8266 turned on 24-7.
Using a Wifi analizer I could narrow it down to my livingroom.
Checked all devices, and they are all connected to my AccessPoint.
(So no fallback AP mode)
The problem with this method is that you can’t figure out a direction.
So I used this on my Laptop.
This is a directional antenna.
Using Wireshark and wavemon, I could find the direction.
There were only two devices in the direction with the strongest signal.
My photo viewer remote, and my mini turntable controller with RFID.
But these devices are working just fine! .. So lets disconnect the power.
So it IS the mini recordplayer!
Lets look at the code. (part of)
WiFi.mode(WIFI_AP_STA);
I should have used
WiFi.mode(WIFI_STA);
Now it was a client AND an Access Point!
Mystery solved!