B4R Tutorials

 

This example downloads a file from a server folder (here I use a folder in htdocs on my apache server) and saves it to a file on the file system. Tested with 700KB files. Set headers (browse the...

 

This is an updated example how to en-/decrypt data with AES256.

Libs needed: jRandomAccessFile only

Notes:

- As far as I know, the ESP32 doesn't support padding like PKCS5/7, so I had to do it...

 

Ola

Code Module - B4r - Queue List [module]
Code Module - B4r - Stack Collection [module]
Code Module - Http - Rhttputils2 - Http Client [module]
Library - Arduino - Radafruit_mcp3008...

 

My office gets cold overnight in winter. I have a heater which has a basic thermostat but its very inaccurate (its just a min/max dial not temperature based). If I leave it on...

 

https://blinky-nina-w102.blogspot.com/2021/04/u-blox-nina-w106-sendo-programado-em_21.html

 

Just for the fun of it. Can now control my Digital Satellite TV decoder from anywhere in my house....
Nano connected to the HC-05 module
B4A app connects to the HC-05 and sends the B4A "button...

 

Arduino Uno with LCD shield:

Working with a LCD monitor:
1. Initialize the LiquidCrystal object and set the connected...

 

 

Here's an advanced ESP32 Now example. The Inlince C code is from several sources (see the inline remarks).

Note: Sometimes there are issues with the Wifi channel (WiFi and ESP Now must use the...

 

I am working on a little thermometer project for my greenhouse using an ESP8266 and a temperature sensor. You have multiple sensors to choose from such as DHT11/22, BMP180 etc, but no...

 

The code was taken from this site: https://randomnerdtutorials.com/esp-now-esp32-arduino-ide/

You need 2 ESP32's (one is the sender, the other one the receiver). Modify the code to have...

 

Here is something pretty handy some times:

Serial oscilloscope – x-io Technologies

x-io.co.uk

(11-3-2021) You can use it with this module in B4R...

 

Based on SSD1306 module, we can display animated images the same as displaying animated GIF on PC. The animated image is a byte array contains (n) number of frames(bitmap images) they all...

 

Based on SSD1306 module, we can implement horizontal and vertical progress bars. These bars could be drawn at X1-Y1 to X2-Y2 like drawing rectangles, also we need to pass the full scale...

 

Programming an ESP-12x module directly is not too difficult. If you purchase an ESP8266 with a built-in USB port like a WeMos D1 Mini or a NodeMCU etc, then you do not need to do this as the...

 

To complete the B4X FTP season (https://www.b4x.com/android/forum/threads/74320/#content) I've written a client in B4R.

It allows to connect to a FTP server and download or upload files...

 

MQTT is an excellent solution for connection of multiple devices.

Tutorial about MQTT: [IoT] MQTT Protocol

The rMQTT library, which is based on PubSubClient open source project, makes...

 

Here is a very interesting video by the guy in Dronebot Workshop. This board seems amazing. I suppose since it is Arduino compatible it can also work with B4R with the exception of the commands...

 

Here is an interesting article for MQTT Broker scalability:

Top 10 IoT Scalability Tests for an MQTT Broker

Describing some key criteria when evaluating MQTT brokers to ensure the successful deployment/operation of an MQTT system.

www.hivemq.com