Ultrasonic UART sensor

corvy · September 19, 2019, 4:21pm

I cannot get my ultrasonic sensor to work, and I cannot seem to understand what I am doing wrong.

This is my code:

esphome:
  name: waste_tank
  platform: ESP32
  board: nodemcu-32s

wifi:
  ssid: "xxx"
  password: "xxx"

# Enable logging
logger:
 
sensor:
  - platform: ultrasonic
    trigger_pin: GPIO5
    echo_pin: GPIO4
    unit_of_measurement: "%"
    icon: "mdi:water-percent"
    accuracy_decimals: 0
    update_interval: 5000ms
    name: "Waste tank"

My log looks like this:

[18:22:05][C][ultrasonic.sensor:035]: Ultrasonic Sensor 'Waste tank'
[18:22:05][C][ultrasonic.sensor:035]:   Unit of Measurement: '%'
[18:22:05][C][ultrasonic.sensor:035]:   Accuracy Decimals: 0
[18:22:05][C][ultrasonic.sensor:035]:   Icon: 'mdi:water-percent'
[18:22:05][C][ultrasonic.sensor:036]:   Echo Pin: GPIO4 (Mode: INPUT)
[18:22:05][C][ultrasonic.sensor:037]:   Trigger Pin: GPIO5 (Mode: OUTPUT)
[18:22:05][C][ultrasonic.sensor:038]:   Pulse time: 10 µs
[18:22:05][C][ultrasonic.sensor:039]:   Timeout: 11661 µs
[18:22:05][C][ultrasonic.sensor:040]:   Update Interval: 5.0s
[18:22:05][C][ota:029]: Over-The-Air Updates:
[18:22:05][C][ota:030]:   Address: waste_tank.local:3232
[18:22:05][C][ota:032]:   Using Password.
[18:22:05][C][api:103]: API Server:
[18:22:05][C][api:104]:   Address: waste_tank.local:6053
[18:22:06][D][ultrasonic.sensor:025]: 'Waste tank' - Distance measurement timed out!
[18:22:06][D][sensor:092]: 'Waste tank': Sending state nan % with 0 decimals of accuracy
[18:22:11][D][ultrasonic.sensor:025]: 'Waste tank' - Distance measurement timed out!
[18:22:11][D][sensor:092]: 'Waste tank': Sending state nan % with 0 decimals of accuracy
[18:22:16][D][ultrasonic.sensor:025]: 'Waste tank' - Distance measurement timed out!
[18:22:16][D][sensor:092]: 'Waste tank': Sending state nan % with 0 decimals of accuracy
[18:22:21][D][ultrasonic.sensor:025]: 'Waste tank' - Distance measurement timed out!

I have tried to swap the echo and trigger, no change. Never once got an echo. Is there some way to measure if I have cabled it correctly with a multimeter or similar?

Short and sweet I have connected the UART Ultrasonic sensor to 5V+ and GND. Trigger to GPIO5 and Echo to GPIO4. Supersimple, or so I thought… My sensor is a waterpoof one documented here: https://github.com/ritesht93/waterproof_small_blind_ultrasonic_sensor_DYP-A02YYxx_v1.0

It is supposed to be 100% compatible with code and cabling for HC-SR04. I have been looking at different guides but mostly used this: https://www.hackster.io/AskSensors/ultrasonic-ranging-with-esp32-and-asksensors-iot-2fafeb. I have also tried the GPIO16 and GPIO17 (RX/TX), but just the same result.

All tips or pointers welcome!

tom_l · September 19, 2019, 11:14pm

You need the PWM version to work with esphome. Not the UART version.

corvy · September 20, 2019, 5:11am

Ok, I was worried that was the case. I will order another

corvy · April 28, 2020, 4:49pm

Hello again @tom_l

I have ordered the PWM one and I still cannot get it to work.

This is the Arduino code: https://github.com/riteshRcH/waterproof_small_blind_ultrasonic_sensor_DYP-A02YYxx_v1.0/blob/d8dcda206587feae70b3fca179b05b50d18549f7/code/arduino/DYPA02YYWM_v1_arduino_uno_code/DYPA02YYWM_v1_arduino_uno_code.ino

Is there some magic I do not understand? I have tried my code with a HC-SR04 and that works fine. When I put my ear to the sensor (the A02YYWM one) I can hear the “tick” of the trigger. But it does not read any data back. Tried also to increase the pulse time but still no cigar.

esphome:
  name: waste_tank_esp32
  platform: ESP32
  board: esp32doit-devkit-v1

wifi:
  ssid: "xxx"
  password: "xxx"

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Waste Tank Esp32"
    password: "xxx"

captive_portal:

# Enable logging
logger:

# Enable Home Assistant API
api:
  password: "xxx"

ota:
  password: "xxx"

sensor:
  - platform: ultrasonic
    trigger_pin: GPIO2
    echo_pin: GPIO4
    name: "depth"
    update_interval: 2s
    pulse_time: 20us

Anything else I should try? I feed it with 5V like it says on the spec. Does the trigger have to ve 5V as-well? Thanks for any help!

Fixed, the code was not quoted correctly.

tom_l · April 28, 2020, 4:50pm

Please format your code correctly.

corvy · April 28, 2020, 5:30pm

Not sure why it ended up like that…

esphome:
  name: waste_tank_esp32
  platform: ESP32
  board: esp32doit-devkit-v1

wifi:
  ssid: "xxx"
  password: "xxx"

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Waste Tank Esp32"
    password: "xxx"

captive_portal:

# Enable logging
logger:

# Enable Home Assistant API
api:
  password: "xxx"

ota:
  password: "xxx"

sensor:
  - platform: ultrasonic
    trigger_pin: GPIO2
    echo_pin: GPIO4
    name: "depth"
    update_interval: 2s
    pulse_time: 20us

tom_l · April 28, 2020, 5:52pm

Are you doing any level shifting on the echo PIN?

The SR04 requires a 5V supply.

3.3V is enough to trigger the measurement to start.

But, the echo pin will pulse 5V into GPi04. It is only rated for 3.3V.

Connect a 4K7 resistor to the SR04 echo pin. Connect a 9K1 resistor from the other end of the 4K7 to ground. The junction of the two resistors goes to GPIO4.

SR04 Echo out> ---------[ 4K7 ]---------●--------[ 9K1 ]------------ GND
                                        |
                                        |
                                      GPIO4

Fingers crossed you have not burnt out the GPIO.

corvy · April 28, 2020, 6:39pm

Ah thanks, good tip. I have more ESPs in case. Will do another test.

corvy · April 29, 2020, 11:42am

I have tried with the resistance to shift the level. I measured with a multimeter and it was down to 3,1V so that should be working well, but still it does not work. Tried to configure the HC-SR04 with the same setup and that works just perfect. So the GPIOs seems to be working fine. Also, just to be 100% sure I replaced the ESP with a new one and I get the same results.

But looking in the data of the sensor I find this.

Does this make a difference? For my eyes it seems that it has a delay on T2 that might be troublesome? Am I wrong?

tom_l · April 29, 2020, 12:34pm

I don’t understand what you are saying here. Is it working or not?

Does what make a difference?

corvy · April 29, 2020, 12:40pm

Yes the HC-SR04 is working, but I am trying the waterprotected version, which is supposed to be 100% compatible. The HC-SR04 is not water protected at all. But I suspect that the sensor I use is not 100% compatible … therefor I link the picture above.

Here is the IP65 sensor:

And this is the Arduino code for the PWM version (which is supposed to be 100% compatible… again, I doubt it).

github.com

riteshRcH/waterproof_small_blind_ultrasonic_sensor_DYP-A02YYxx_v1.0/blob/d8dcda206587feae70b3fca179b05b50d18549f7/code/arduino/DYPA02YYWM_v1_arduino_uno_code/DYPA02YYWM_v1_arduino_uno_code.ino

/**
 * 
 * Author: Ritesh Talreja, Made in China, Warehouse: Shenzhen, Guangdong.
 * 
 * Components: Arduino UNO, DYPA02YYWM  v1.0
 * 
 * Arduino UNO +5V    --> DYPA02YYUM Pin 1 Red
 * Arduino UNO GND    --> DYPA02YYUM Pin 2 Black
 * Arduino UNO Pin 11 --> DYPA02YYUM Pin 3
 * Arduino UNO Pin 10 --> DYPA02YYUM Pin 4
 * 
 */

#define TRIGGER_PIN 11
#define PWM_OUTPUT_PIN 10

long duration;
float distance;

void setup()

This file has been truncated. show original

So sadly it does not work for my application (measurement of waste water inside a tank).

corvy · April 29, 2020, 12:42pm

Just to be 100% clear. I have tried the HC-SR04 and the DYPA02YY sensor on the same ESP (one at a time) with the same code. Both with 3,3V and with 5V power supply. The HC-SR04 works fine, but not the DYPA02YY. So what I am looking for is to try and debug the difference of these sensors…

tom_l · April 29, 2020, 12:47pm

Right! Now I’m with you. I’ll have a look at the two data sheets after dinner.

tom_l · April 29, 2020, 2:32pm

Looks to be compatible. Which pin are you using as Trigger, Tx or Rx?

corvy · April 29, 2020, 2:48pm

I use D2 as trigger. Connected to the third pin on the ultrasonic sensor. The last wire connected via the resistor to give 3V back to D4.

corvy · April 29, 2020, 2:53pm

tom_l · April 29, 2020, 3:00pm

Yeah, that’s not what I meant. The sealed transducer has two data pins, Tx and Rx. Which one are you using as the trigger?

juan11perez · April 29, 2020, 3:03pm

not sure if it may help you, but I’ll share.
I’ve been using this sensor with a wemosd1 without any resistors for about 2 years with tasmota.
The tasmota sensors.bin already include this sensor.
just pick your pins, connect and thats it.

corvy · April 29, 2020, 3:26pm

In the code above they list all the pins in the same order as they are on the connector. I use the third pin as trigger and the fourth as echo.

corvy · April 29, 2020, 3:32pm

Is this the same IP65 one that I am using? Or are you using the SR04?