MQTT learning on Pi with BME280 and node-red, node-red-dashboard

install on pi using apt
https://randomnerdtutorials.com/how-to-install-mosquitto-broker-on-raspberry-pi/
testing mqtt with pi terminal
https://randomnerdtutorials.com/testing-mosquitto-broker-and-client-on-raspbbery-pi/
using esp32
https://randomnerdtutorials.com/esp32-mqtt-publish-subscribe-arduino-ide/




becareful with the BME280 board, I have 2 kinds of board, one with a square sensor on it, this one works with adafruit library, the other one with a rectangle one, this one does not work with most of BME280 libs.

there is a post, saying adafruit library checks CHIPID of 280:
http://davidstein.cz/2017/09/30/arduino-bme280-could-not-find-a-valid-bme280-sensor-solved/
I followed it and sensor start to work.
the default address used in adafruit is 0x77, if you use 0x76, then use this:
   status = bme.begin(0x76);
Below both with default ID=0x76, the purple ones works finally, but no humidity reading with the example of adafruit, the blue one reads humidity with same code.

Image result for bme280Image result for bme280




also you need a PubSubClient library
Click here to download the PubSubClient library. You should have a .zip folder in your Downloads folder

 the example  https://github.com/RuiSantosdotme/Random-Nerd-Tutorials/raw/master/Projects/ESP32-MQTT/ESP32_MQTT_Publish_Subscribe.ino

 publish temp in esp32/temperature and humidity in esp32/humidity
all numbers need to be convert to array.

 you can use terminal on pi to subscribe:
mosquitto_sub -d -t esp32/temperature

 node-Red cames with the image of pi, but you need to start it on pi.
but not in the lite version, use this to install node-red
https://randomnerdtutorials.com/getting-started-with-node-red-on-raspberry-pi/

bash <(curl -sL https://raw.githubusercontent.com/node-red/raspbian-deb-package/master/resources/update-nodejs-and-nodered)
node-Red dash board is not installed, need to install separately.
https://randomnerdtutorials.com/getting-started-with-node-red-dashboard/

and config the group to show in dash board

almost

留言

張貼留言

這個網誌中的熱門文章

Heltec ESP32+OLED+Lora, hardware testing

圖片
you can easily find some good boards from china, but most of them lack of accurate document... Hrere is an example; https://hackaday.io/project/26991-esp32-board-wifi-lora-32 the board looks good with lora and a 128x64 OLED, but the IIC and reset connection is important, since pin can be muxing easily, so every board could be different. pinMode(16,OUTPUT);  digitalWrite(16, LOW); // set GPIO16 low to reset OLED  delay(50);  digitalWrite(16, HIGH); // while OLED is running, must set GPIO16 to high  and, if needed, edit your Wire.begin() to Wire.begin(4,15); (4 = SDA 15 SCL)  i tested it with the Adafruit SSD1306 and the Acrobotics SSD1306 Librarys  both work.  Display size is 128x64 There are discussions on these boards on TＴＮ as a LORA node..or maybee single ch gateway? Heltec has a git :  https://github.com/Heltec-Aaron-Lee And there is another copy call TTGO https://de.aliexpress.com/item/TTGO-LORA32-868-915-Mhz-S...
閱讀完整內容

micro SD card for ESP32, on lolin32 with OLED and heltec 32 lora oled

圖片
I have purchased 2 micro SD card holder for my esp project. First I would like to test with heltec esp32 lora oled module. this module uses: sck=05 MISO=19 MOSI=27 SS(lora)=18, then I assigned 21 for sd SS and there is a lib in esp32-arduino, which use SS default at 5 I took the example and use SD.begin(21), but I alway get the error: entry 0x40078a9c Card Mount Failed But I do saw once that it read out the sd card type and volume. Not sure it's the issue of lora sd card swithing, or it just can't work. The other esp32 card I have is an wemos esp32 oled, it did not leave me too much pins, I need to find out how to connect sd to it. But I have wemos D1 mini esp8266 on hand, and connect it as:  * The WeMos Micro SD Shield uses:  * D5, D6, D7, D8, 3V3 and G  *  * The shield uses SPI bus pins:  * D5 = CLK  * D6 = MISO  * D7 = MOSI  * D8 = CS It's not working with the example in the arduino IDE 1.8.5, which m...
閱讀完整內容

AIS0. understanding AIS NMEA 0183: How it's coded

For my boat tracking system, I found out that using AIS format seems to be a good idea, at least I don't have to worry about how to present boat data, since there are already plenty things for do this on mobile phone or PC. Here is what I read: http://catb.org/gpsd/AIVDM.html Looking into AIS NMEA0183, it has much more application then I think. Such as MOB device, epir, aid to navigation device...etc, all are included. it use the first few char to indicate the function: Table 1. AIS talker IDs !AB NMEA 4.0 Base AIS station !AD MMEA 4.0 Dependent AIS Base Station !AI Mobile AIS station !AN NMEA 4.0 Aid to Navigation AIS station !AR NMEA 4.0 AIS Receiving Station !AS NMEA 4.0 Limited Base Station !AT NMEA 4.0 AIS Transmitting Station !AX NMEA 4.0 Repeater AIS station !BS Base AIS station (deprecated in NMEA 4.0) !SA NMEA 4.0 Physical Shore AIS Station It can also be used between device on boat for message communication, AIVDO The...
閱讀完整內容