Bendyroad IDE reference manual

Index

Blocks

• AVRdude override
• Analog input
• Arduino LCD Keypad Shield
• Arduino Mega board
• Arduino Uno board
• BH1750 light sensor
• Blinker
• Data transmission
• Deadband
• Debounce
• Debounced Switch
• Derived variable
• Digital input
• Digital output
• ESP tool override
• ESP32-S3
• GY-30 light sensor
• Global variable
• Hardware Folder
• IDE Preferences
• Indicator
• Keyboard handler
• LCD Display
• LED
• Logic Folder
• MQTT
• MQTT configuration
• OS ticks
• Optimizer hints
• PWM LED
• Page
• Programmer options
• Programmer settings
• Project
• Project info
• RGB LED
• Reporting field
• Rule
• SP5055
• Schmitt-Trigger
• Screen Page
• Serial TLV
• Settings
• Settings item
• Settings screen
• Startup banner
• System activity LED
• Telemetry var mapping
• Telemetry var wildcard
• Text field
• Timer
• Variable and label
• Variable field
• Wifi configuration

Topics

• Block name
• Disable
• Expressions
• Free to use fields
• Pin
• Rules
• Screens
• Telemetry
• Types

Objects

AVRdude override

To override the system defaults with a specific AVRdude command line.

When you want to use your own avrdude-like tool.

Analog input

Read analog values from a CPU pin.

See also: Example: Ambiant temperature measurement with a TMP36 sensor.

Arduino LCD Keypad Shield

No info available, yet.

Arduino Mega board

Arduino Mega board.

See also: Arduino Mega implementation notes

Arduino Uno board

Arduino Uno board.

See also: Arduino Uno implementation notes

BH1750 light sensor

The BH1750 is a light sensor that directly outputs illuminance in lux.

It communicates via I²C interface, making it compatible with many microcontrollers. With a wide range and high precision, it's commonly used in lighting control, mobile phones, and weather stations to measure environmental light levels.

Blinker

See also: Example: Blinking LED

The primary function of the Blinker block is to control the timing of on-off cycles. It can be programmed to switch any compatible device on and off at specified intervals, measured in milliseconds.

When the time is 500 milliseconds, the blinker blinks once per second. 500ms on and 500ms off.

Data transmission

You configure Telecommand & Telemetry here.

See how all this works together in Telemetry.

Deadband

Deadband is a concept referring to a range of input values that do not produce any change in the output. Deadband is used to prevent system instability or unnecessary frequent oscillations, such as a thermostat not turning a heater on and off for minor temperature fluctuations.

Example:

A thermostat is set to maintain the room temperature at 20 degrees Celsius. To avoid the heater turning on or off for every tiny temperature change, it can be given a deadband of, for example, 1 degree.
That way, a temperature drop to 19.9 degrees will not turn on the heater, but a temperature drop to 19.0 or lower will.

Debounce

To de-bounce an input source, like a switch or a pushbutton.

To make sure a switch connection or button push registers only once it's firmly made.

The debounce functionality is already included in the Debounced Switch block.

Debounced Switch

Hardware switch to ground, with cpu internal pull-up. Software debounced. (1=switch pressed).

Digital input is commonly used to detect the state of switches and buttons. This block also includes the debouncing (See also: Debounce) of the switch or button.

See also: Example: A simple switch and LED.

Derived variable

No info available, yet.

Digital input

A single input pin on the CPU.

It can have an optional pull-up.

The naming is dependent on the processor or platform.

For instance, on Arduino it looks like: "D2".

Digital output

A single output pin on the CPU.

ESP tool override

To override the system defaults with a specific ESP-tool command line.

When you want to use your own ESP-tool-like tool.

ESP32-S3

The ESP32-S3 processor.

See also: ESP32-S3 Implementation notes

GY-30 light sensor

The GY-30, is a module with the BH1750. It is a digital ambient light sensor that provides precise light intensity measurements.

Operating via the I²C interface, it's often integrated into electronics projects, enabling devices to respond to changing light conditions.

Global variable

No info available, yet.

Hardware Folder

A folder can be used to logically group blocks together.

If you disable a folder, all blocks in it are also disabled.

IDE Preferences

This contains all the settings, private to your IDE. Shared between all the projects you use on this workstation.

Indicator

Read about how this works with other screen elements in Screens.

Displays the text belonging to the first expression that is non-zero.

Keyboard handler

Add this for keyboard.

LCD Display

For connecting a generic LCD display.

You have to assign the pins to this display component.

• Register Select (0 = command, 1 = data)
• E: Enable
• DB0~DB3: Display data signal; lower byte in 8-bit mode

And the size of the display in rows and columns

• Number of columns
• Number of rows

Next, define what to show in Screens.

LED

A LED connected to a CPU output pin.

An alias for Digital output .

Logic Folder

A folder can be used to logically group blocks together.

If you disable a folder, all blocks in it are also disabled.

MQTT

Enable MQTT telemetry.

Is only available on systems with an network connection.

MQTT configuration

To configure the MQTT configuration of the controller direct after programming it.

Example:

mqtt://192.168.1.10

or

mqtts://my.mqtt:1245/

OS ticks

No info available, yet.

Optimizer hints

To set preferences for the optimization by the firmware generator.

PWM LED

A dimmable LED.

The brightness is specified in percentage. It ranges from 0 (off) to 100 (full on).

See also: Example: Dimmable LED (PWM)

Page

No info available, yet.

Programmer options

Here you configure the target programmer.

The defaults are probably fine, but if you want to use your own programmer program, or use special options, you can configure this here.

Programmer settings

Programmer settings local to this PC.

An menu option for searching the programmer is available for certain programmers.

Project

This represents the top of the project file.

Project info

This is only to document your project.

All the fields are for your own administration. They are shown in the generated documentation (if your subscription includes this option).

All fields are optional, you can leave them empty.

RGB LED

A RGB LED connected to 3 output pins on the CPU.

Functions the same as 3 PWM LEDs.

Usage

Specify the pins for each colour, and give it a name, for example 'rgb_led'.

Each colour can be set to intensity 0 (off), 25, 50, 75 or 100 (full on), in a logic block.

For example, a logic rule 'set_magenta':

rgb_led.red = 50;
rgb_led.blue = 50;

Because RGB LEDs work with intensity settings from 0 to 100, and Blinker works with on and off only, RGB LEDs can't be used with blinkers.

Reporting field

See how all this works together in Telemetry.

Rule

A rule is as block of text with a 'C', Javascript like language to describe logic rules.

For more on rules, see: Rules.

SP5055

Single chip frequency synthesizer, I2C.

Schmitt-Trigger

A Schmitt trigger converts varying analogue inputs into binary outputs with defined thresholds.

It provides noise immunity and hysteresis, preventing rapid switching and ensuring stable signal processing.

Screen Page

A page on a screen.

Read about how this works with other screen elements in Screens.

Serial TLV

Telemetry via a serial connection.

Settings

This is a special screen page definition. It represents a menu driven system for configuring variables within the device.

Settings item

Read about how this works with other screen elements in Screens.

Settings screen

This is a special screen page definition. It represents a menu driven system for configuring variables within the device.

Read about how this works with other screen elements in Screens.

Startup banner

No info available, yet.

System activity LED

This represents a GPIO port that connects to a LED thats lit when the system is active.

In a normal system this looks like a high frequency repeated flash, or dimmed LED.

Telemetry var mapping

See how all this works together in Telemetry.

Telemetry var wildcard

See how all this works together in Telemetry.

Text field

Read about how this works with other screen elements in Screens.

Timer

No info available, yet.

Variable and label

Read about how this works with other screen elements in Screens.

Variable field

Read about how this works with other screen elements in Screens.

Wifi configuration

To configure the Wifi configuration of the controller direct after programming it.

Topics

Block name

Most blocks have a name. Usually this forms the base of variable names exposed with the block.

For example a sensor measuring temperature and light, with a name 'sensor' the variables exposed would be 'sensor.light' and 'sensor.temp'.

Disable

With disable you can (temporary) exclude a block.

This allows you to quickly exclude parts of the program, for example when testing incomplete hardware.

Also when a folder is disabled, all the blocks inside this folder are also excluded.

Expressions

See: Rules reference.

Free to use fields

There are some fields for your own use.

It has no effect on the generated firmware.

These can be used in documentation, or to make note of important things.

Like:

• Comment
• Project id
• Customer name

Pin

A pin is a pin on the controller/cpu.

Also known as GPIO (General Purpose IO).

The names follow a platform specific convention.

Arduino platform

For Arduino platform it looks like:

A8 = Analog port 8
D2 = Digital port 2

You can also use AVR8 notation, when the Arduino has a AVR8 cpu.

AVR8 platform

For AVR8 platform it looks like:

PD0 = Pin 0 on port D.
PB2 = Pin 2 on port B.

Rules

A rule is as block of text with a 'C', Javascript like language to describe logic rules.

See also: Rules reference.

Example:

if ( temp > 25  ) {
    fan = 1 ;
} else {
    fan = 0 ;
}

Screens

Screens is a way to define your screens.

Screens are presented as pages.

Changing pages can be by user control, or program control, or both.

Only 1 page at a time is shown.

Settings page

Settings is a predefined page to edit settings.

Screen page

A normal screenpage consists of labels and fields.

Labels are fixed texts

Fields are dynamic texts, presenting values from variables.

A screenpage is divided in a grid. The origin of the grid is top-left. The grid starts counting with 0,0.

Telemetry

Telemetry is the process of transmitting data from a device to a remote system for monitoring and analysis.

This is useful for monitoring, saving sensor values in a database, make graphs, and many more applications.

Telemetry routing

Here you specify which transport to use for the telemetry.

• Serial
• MQTT

Telemetry var mapping

This is the folder containing the "Reporting field" items. These specify which variable to send.

Reporting field

To add a value to the data stream, enter the name of the variable (this can be a sensor that you have defined in the Hardware folder) and the tag that you want to assign to it.

The tag is a numeric value, you choose, to give an unique id to the value in the case when the transport mechanism is not able to send texts.

Types

Each of these data types serves a specific purpose and can be used to optimize memory usage and computational performance in your system.

Bits

A BIT represents a binary digit, which is the smallest unit of data in a computer system. It can hold one of two values.

Integer

"Signed" means it can represent both positive and negative values.

"Unsigned" means it can only represent non-negative whole numbers.

Floating

Floating point numbers are designed to represent real numbers, allowing for a wide range of values with varying degrees of precision. The range and precision of these numbers depends on the specific implementation.

See also: The use of Floating-Point Values in Embedded Applications.

Misc documents

9-in-1 Sensor Shield

The 9-in-1 Sensor Shield is a multifunctional module designed for easy interfacing with various sensors. It enables rapid prototyping by providing a streamlined interface for multiple input and output devices. Key features include temperature, humidity, light, sound, and motion sensors, among others. Ideal for Arduino-based DIY projects and education.

Pinning

Arduino Mega implementation notes

See also:

• Arduino Mega datasheet

Pin naming

You can use the Arduino's convention for naming IO ports, such as 'A1' for analog pins and 'D20' for digital pins. It starts counting with A0 and D0.

Telemetry

There is only serial telemetry available because of lacking internet supporting hardware.

Arduino Nano implementation notes

See also:

• Arduino Nano datasheet

Pin naming

You can use the Arduino's convention for naming IO ports, such as 'A1' for analog pins and 'D20' for digital pins. It starts counting with A0 and D0.

Telemetry

There is only serial telemetry available because of lacking internet supporting hardware.

Arduino Uno implementation notes

See also:

• Arduino Uno datasheet

Pin naming

You can use the Arduino's convention for naming IO ports, such as 'A1' for analog pins and 'D20' for digital pins. It starts counting with A0 and D0.

Telemetry

There is only serial telemetry available because of lacking internet supporting hardware.

Block name

Most blocks have a name. Usually this forms the base of variable names exposed with the block.

For example a sensor measuring temperature and light, with a name 'sensor' the variables exposed would be 'sensor.light' and 'sensor.temp'.

Condition examples

Testing for a condition

Equals

if( a == 10 ) { q = 1 ; }

Not equal

if( a != 10 ) { q = 1 ; }

Greater than

if( a > 10 ) { q = 1 ; }

Greater than or equal

if( a >= 10 ) { q = 1 ; }

Less than

if( a < 10 ) { q = 1 ; }

Less than or equal

if( a <= 10 ) { q = 1 ; }

Disable

With disable you can (temporary) exclude a block.

This allows you to quickly exclude parts of the program, for example when testing incomplete hardware.

Also when a folder is disabled, all the blocks inside this folder are also excluded.

ESP32-S3 Implementation notes

See also:

• ESP32-S3 datasheet

Disabled ADC2

The ESP32-S3 Errata sheet provides a warning against the use of the ADC2. Due to this warning, we have decided to exclude the use of the ADC2 in our implementation.

Currently implemented

• GPIO
• TWI
• ADC
• MQTT
• WIFI

Example: A simple switch and LED

• the switch has the 'name': 'sw1'
• and connected to 'port' 'D11' (or any other port you chose)
• use the current value of 'sw1' in a rule, for example

set a LED on when sw1 is on:

if ( sw1 ) {
    led1 = 1 ;
} else {
    led1 = 0 ;
}

Example: Air quality alerting with a MQ135 sensor

The MQ-135 sensor detects harmful gases in the air, such aas NH3, NOx, alcohol, and benzene.

The sensing element reacts to concentrations of certain gases by changing its resistance.

Hardware setup

To wire the gas sensor up to an Arduino, connect the VCC and GND appropriately, and the signal wire to an analog pin, in this example pin 0.

Making the firmware

In this example, we're using a threshold value of '200'. When the sensed value is greater than that, the on-board LED is turned on.

Instead of turning on a LED, you can sound a buzzer or start a fan motor.

This screenprint shows all there is to it: a sensor defined, and a basic logic rule to switch the LED on or off depending on the sensor value.

Example: Ambiant temperature measurement with a TMP36 sensor

Introducing the TMP36 sensor, a versatile analog device renowned for its linear temperature-to-voltage output. This guide offers a step-by-step approach on interfacing the sensor with an Arduino, processing its readings, and implementing logic based on the derived temperature.

The TMP36 sensor (and TMP35 and TMP37) provide a voltage output that is linearly proportional to the temperature in Celsius.

Hardware setup

To wire the temperature sensor up to an Arduino, connect the VCC and GND appropriately, and the signal wire to an analog pin, in this example pin 0. In this picture, the flat part of the package is shown in front. Make sure what the pinout is of the sensor you are using, by checking the documentation that belongs to it.

Making the firmware

To illustrate the use of the concept of [[Variables|Derived variables]], we're calculating the temperature in degrees Celcius.

Next, a rule is used: when the temperature is higher than 18 C, the on-board LED is turned on. Surely you'll want to do something more useful, for example turning on the heating, the LED is just to illustrate the idea.

That's all there is to it: a sensor, calculating the temperature, and basic logic rule to switch the LED on or off depending on the temperature.

It becomes a lot more interesting once you start using Settings to change the temperature setting using a Arduino LCD Keypad Shield and Keyboard handler.

Example: Blinking LED

Download program: blink.prg

This program consists of a blinker to drive the blinking cycle. Followed by a logic rule to connect the blinker value to the led. The led is included on the Arduino board.

The blinker time parameter is the time the blinker value is '1'. So 500ms gives a blink cycle with 500ms on, and 500ms off.

Example: Dimmable LED (PWM)

Is in preparation.

Expressions

See: Rules reference.

Free to use fields

There are some fields for your own use.

It has no effect on the generated firmware.

These can be used in documentation, or to make note of important things.

Like:

• Comment
• Project id
• Customer name

Getting started

Installing BrainBuilder Development Studio

If you haven't installed yet, go to: Installation.

Starting the Development Studio

Click on the menu entry or desktop icon for the BendyRoad IDE.

On first startup, you may find it a little too grayish, so you can choose a different skin:

Exploring the built-in example

Under 'File', 'Example' is the classic "hello world" of firmware: the blinking LED.

Connecting a development board

The example is for the Arduino Uno, but it is easily changed for other development boards. More on that later.

Go to 'Target', then 'Search programmer' to start the autoscan for a development board. Sometimes it can take a while to try a few ports before the board is found. (Only one connected board at the same time is supported)

Generating the firmware

Go to 'Target', then 'Generate' to generate the example

The first time you use BrainBuilder, a browser window will open to link your workstation.

Once the workstation is linked, the firmware is generated. Linking is a one-time thing, so the next times you generate firmware, it will be immediate.

After a few seconds the firmware is generated, flashed, and running on the development board.

Changing the example

It's a good start to change the frequency of the 'blink', generate again, and see your change become effective quickly.

Saving the project file

It's convenient to create a folder to store your projects in. The folder is remembered for the next times you start BrainBuilder.

Starting a new project

When starting a new project from scratch, always start by adding a development board (left-click on the 'Hardware' folder). For example an Arduino Mega board.

You can change the automatically assigned name to a name that is meaningful to you. The on-board LED is also assigned a default name that you can change. Note that in the list of variables on the left, 'led1' has been added as a variable of type 'bit'.

Click on 'Show hints'/'Hide hints' to toggle descriptions of all the fields on this panel on or off, or click on any individual field to view only a hint about that field.

Adding more hardware

Display

If you have a Arduino Display shield or a generic LCD Display, you can add that too in the same way.

LEDs

Arduino Uno and Mega have an on-board LED that is already configured and available as 'led1'. Other LEDs you can add yourself.

Input

With analog and digital inputs, you can define which sensors or switches are connected to which pins.

Example: For using an analog temperature sensor on analog input pin 2, use an Analog Input block, name it 'temp' and specify the port as '2'.

This automatically adds the variable temp. The list of variables on the right-hand side of the screen is updated with the new variable.

Output

Example: A switch connected to Digital Output port 'D12'

Logic

Rule blocks specify actions based on conditions. For example, to switch 'led2' on when 'temp' level over 23, and off if is below, add a rule like this:

if ( temp > 23 ) {
    led2 = 1;
} else {
    led2 = 0 ;
}

Global variables

Input blocks implicitly make variables available with the name of that block. For example 'Light'. But if it is easier to work with the inverse value, we can define a Global Variable with the name 'LightInverted' and type U16. Then we can add a Rule Block to set the variable 'LightInverted' to '1024 - Light'.

Output

If you have a LCD connected to your Arduino, add it as a hardware item:

Next, add a 'Screen' under 'Screen Definitions'. This will create a 'Screen Item List', to which you can add 'Screen cells'.

A screen cell is the easiest way to display a text and a value together.

For example, to show the ADC value from the temperature sensor on the display, specify text 'Temp.: ', and a value from a temperature sensor (temp).

The Arduino display has two rows of 16 characters. Numbering starts at 0. An easy way to get the lay-out correct is to use grid paper.

You can enter project information on the Project Info page. There's room for a description and notes.

Reordering blocks

You can drag and drop blocks to reorder them, and organize them in folders, to logically group blocks together.

Glossary

Term:

Target

Definition:

A "target" refers to the specific hardware platform or device that the embedded software is designed to run on. This includes arduino, microcontrollers, microprocessors, or any other type of embedded system.

IDE concepts

Here we describe the graphical concepts and items that are part of the BrainBuilder IDE.

Top menu bar

• File: for saving and opening projects
• Options: development board programmer type
• Firmware: to generate the new firmware and flash it the development board
• Cloud: to log in and out
• Tools: to autodetect the port where the development board is connected to
• Help: opens a browser with the documentation site

Left Sidebar / Project tree

This is were you find all the blocks grouped in the main folders (Project Info, Miscellaneous, Hardware, Logic, Screens).

Right Sidebar / Variable list

Here you'll find a list of variables for easy reference. It is maintained automatically.

ToDo info area

This lists the next actions to do. For example when starting a new project, the first thing to do is adding a development board. This will be shown here as a 'to do' item.

Installation

Installation on Windows

Installation on Mac OS

Installation on Debian/Ubuntu

Installation on Linux with snap

Installation on Debian/Ubuntu

Steps to get ready to run BrainBuilder Development Studio for the first time:

Prerequisites

Check the minimum system requirements:

• Ubuntu 20.04 (Focal Fossa) (or newer), Debian Stable/Buster/10.9
• Display size 1024 x 768
• All security updates installed

You may be able to use other versions, but we do not test these. If you run into problems when using other versions, you have to fix them yourself.

Install BendyRoad IDE

Download the BrainBuilder Development Studio Linux installer package.

Install the package:

sudo dpkg -i ./brainbuilder_[version]_amd64.deb

Install avrdude

BrainBuilder makes use of AVRDude. If it is not already installed, install it:

sudo apt install avrdude

Check if avrdude has been installed correctly:

avrdude -?

This should display the help for avrdude.

Check group membership for accessing your development board

Connect your development board

Look up by which group it is owned:

ls -l /dev/tty*

The one to look out for will be named /dev/ttyUSB[number] or /dev/ttyACM[number], for example:

crw-rw----+ 1 root dialout 188,  0 nov  9 10:05 /dev/ttyUSB0

Usually the group it belongs to, is group 'dialout'. Check if you are a member:

groups

Add yourself to the 'dialout' group if you are not a member:

sudo usermod -a -G dialout [your user name]

Start the BrainBuilder Development Studio

Start BrainBuilder from the menu (Programming):

Or create a desktop shortcut for:

/opt/brainbuilder/bin/brainbuilder

Or start BrainBuilder from a terminal window, add /opt/brainbuilder/bin/ to PATH, whichever you prefer

Start creating!

• Connect your development board
• Continue to Getting started

Installation on Linux with snap

Click on [Get it from the Snap Store] in the above image, and follow the instructions.

sudo snap connect bendyroad:raw-usb

Menu entry

A menu entry for BendyRoad will be created in the "Other" category.

Start creating!

• Connect your development board
• Continue to Getting started

Installation on Mac OS

Steps to get ready to run BrainBuilder Development Studio for the first time:

Prerequisites

Check minimum system requirements:

• macOS Catalina / Ventrua (Intel-based)

You may be able to use other versions, but we do not test these. If you run into problems when using other versions, you have to fix them yourself.

Download & Installation

Download the BrainBuilder Development Studio MacOS installer package.

Open the 'Downloads' folder in Finder.

Right-click on brainbuilder-[version].pkg, and choose menuitem Open with [Installer].

A warning pops up, click [Open]. The installer starts (if nothing seems to happen, it will be behind the Finder window).

After 'The installation was successful', click [Close]. You can now move the installer package to the Trash bin.

Starting the Development Studio

You'll find BrainBuilder in the Finder under Applications. Double-click it to start the Development Studio.

For easy access, you can drag the BrainBuilder icon from Finder/Applications or from the Launchpad to the Dock.

Start creating!

• Connect your development board
• Continue to Getting started

Installation on Windows

Steps to get ready to run BrainBuilder Development Studio for the first time:

Prerequisites

Check minimum system requirements:

• Windows 10 or 11.
• Display size at least 1024 x 768
• All security updates installed

You may be able to use other versions, but we do not test these. If you run into problems when using other versions, you have to fix them yourself.

Download & Installation

To begin the installation process, download the BrainBuilder Development Studio Windows installer package and save it.

Once the download is complete, navigate to the Downloads folder and double-click on the downloaded Windows Installer (brainbuilder-[version].msi) file to start the installation.

At this point, Windows may display a warning message stating "Windows protected your PC". To proceed, click on [More info].

Next, click on [Run Anyway] to initiate the installer.

You will be prompted to read and accept the terms of the license. Click [Yes, I accept] to proceed.

Once the installation is finished, you will find an icon for BrainBuilder on your desktop.

To launch the Development Studio, simply click on the BrainBuilder icon.

Start creating!

• Connect your development board
• Continue to Getting started

Interactive treelights

It's the festive season! So I made this interactive tree to brighten and cheer up to my desk. It senses that I'm there, reacts when I talk to it (I like to think so, but in reality it reacts to any loud enough noise) and switches off when I leave.

There is much more to it than being a pretty ornament: it showcases how BrainBuilder supports the use of multiple timers. No less than five independent timers are in use here.

Materials used

• Arduino Mega (or Uno)
• FC-04 sound detector
• Passive infrared sensor HC-SR501
• A light sensor

Light sensor

A GY-30 I2C light sensor module, or an analog light sensor (LDR) works just as well, if using an LDR you'll also need a 10K resistor

For the lights

• 6 LEDs, size 3mm, in 3 colors (colors not a requirement)
• 3 100 Ohm resistors
• wire
• 3 breadboard jumper wires
• heat-shrink tubing

If you are sure you will always use all three LED-strings together, you can connect the three ground wires together. I wasn't sure so I made them suitable for separate use. You may have to tweak the resistor values to get equal amounts of light from the different colour LEDs.

Assembly

First I tested if the LEDs were OK, and if two LEDs in series could be driven from one digital output. Then I marked the long (anode) leads before bending and trimming them. Then prepared 2 long pieces and 1 short piece of wire for each 2-LED 'string'. I sacrificed one breadboard jumper wire to create two plugs on either end of the long wires. Then I put the pieces of heat-shrink tubing in place. Soldered everything together like this:

half a jumper wire - resistor - long wire - LED 1 - short wire - LED 2 - long wire - other half of jumper wire

And tested the assembled LED'string', so I was sure it was working before using the hot air on the heat-shrink tubing. I could say the tubing enhances aesthetics, but it's also great to hide soldering work - I need that ;-)

Configuring the tree

Assembling the hardware took the most time, but from here on, you're almost done. Making the firmware with BrainBuilder is super quick.

Functions of the firmware

The PIR sensor is triggered by changes in its infrared view of the world. A human is much warmer than the surrounding environment, so whenever I move, the sensor 'sees' it. For more information see: Notes on the HC-SR501 PIR sensor.

The red LEDs blink for a while whenever I move. The sound sensor responds to sound waves (it is a very basic thing, it cannot distinguish frequency, or record speech), but it can detect an increase of noise. When there is enough noise, the green LEDs blink for some time. Whether it's me talking, or enthusiastic co-workers, doesn't matter. And then there is the light sensor, that I set up to enable the blinking yellow LEDs as long as there is ambient light. If it is completely dark, all LEDs are off.

Initially I wanted the LEDs off when it was silent AND dark AND no movement, but that can be annoying and/or provoke undesirable reactions by pets. It is easy enough to change.

Experiment with it

Download the example program: xmastree.prg and save the file 'xmastree.prg' in your BrainBuilder Development Studio work directory.

Start the BrainBuilder Development Studio and open the example.

Check if the right development board is specified; that's under 'Hardware', default is an Arduino Mega. If you use an Arduino Uno, delete the Arduino Mega (right-click, then delete), and add an Arduino Uno, and give a name to the Mega.

If you want to change any of the default settings or behavior, change them in the Development Studio.

More ideas

• More or other sensors; for example temperature or VOCs (Volatile Organic Compounds, ethanol is one)
• Using RGB LEDs

Menu help

File

For saving and opening projects

Options

Skin

Here you choose what kind of colorscheme the application should use.

Target

All the actions related to the microcontroller target.

Generate only

Only generate the files and download them to the IDE.

Generate and flash

Do everything, generate, download, send to the microcontroller, and configure the microcontroller.

Flash existing

Only send the firmware to the microcontroller.

Configure target

Only send the configuration to the microcontroller, when you have configured any.

View telemetry

Show the telemetry window.

Search the programmer

Not all platforms find the microcontroller without assistance. This is to check multiple ports for a connected microcontroller of the correct type.

Cloud

All the actions related to the IDE cloud connection.

Connect

To connect the IDE to the cloud generator.

Disconnect

To disconnect the IDE from the cloud generator.

Install

All the actions related to installing utilities.

Help

All help and information related actions.

Online manual

Brings you straight to the online documentation index. It contains a lot more reading material than the builtin help.

Also activated with the hotkey <Ctrl>-H.

Show help

Activated the builtin help window. Also activated with 'F1'.

Third party licenses

Bendyroad makes use of thirdparty libraries. Here you can find the licenses we used to distribute them to you.

JDK licenses

Bendyroad makes use of java. Here you can find the licenses we used to distribute it to you.

About

Here you can find version info, author info and a link to our website.

Notes on the HC-SR501 PIR sensor

The HC-SR501 is a device that connects to a BrainBuilder digital input.

Passive infrared have a very wide field of view and 'see' infrared. In the right-most picture the 'image sensor' is shown. In normal use the image sensor is behind the white plastic 'lens'. They are very good at detecting movement by objects and life forms that are warmer than their surroundings.

If something changes in their view, the output signal is set to 'high'.

Settings

Finding the right settings for the potentiometers may require some experimentation to get them exactly right for your application.

Sensitivity

The sensitivity can be adjusted from 3 meters (potentiometer fully clockwise) to 7 meters (fully counter-clockwise)

Time delay

The time delay can be adjusted from 5 minutes (potentiometer fully clockwise) to 3 seconds (fully counter-clockwise)

Trigger mode

Single-trigger mode ('L'): after motion has been detected, output is set high for the duration of one time delay period only. Repeatable trigger mode ('R'): in addition, motion detected during the time delay period starts the time delay again.

Pin

A pin is a pin on the controller/cpu.

Also known as GPIO (General Purpose IO).

The names follow a platform specific convention.

Arduino platform

For Arduino platform it looks like:

A8 = Analog port 8
D2 = Digital port 2

You can also use AVR8 notation, when the Arduino has a AVR8 cpu.

AVR8 platform

For AVR8 platform it looks like:

PD0 = Pin 0 on port D.
PB2 = Pin 2 on port B.

Rules

A rule is as block of text with a 'C', Javascript like language to describe logic rules.

See also: Rules reference.

Example:

if ( temp > 25  ) {
    fan = 1 ;
} else {
    fan = 0 ;
}

Rules reference

The decision logic is specified in multiple rules.

Rule

A rule consists of a list of one or more statements.

Statement

A statement always ends with a ';' semi-colon. Multiple statements can be combined.

Example:

<statement> ; <statement> ;

or:

<statement> ;
<statement> ;

There are 2 kinds of statements:

• if-statement
• assignment

The 'if' statement

An "if" statement can have the following forms ;

if( <expression> ) { <statements> } else { <statements> };

if( <expression> ) { <statements> } ;

The else part is optional.

If the expression evaluates to non-zero the first statements will be executed.

If the expression evaluates to zero the next list of statements will be executed. The 'else' part of the if statement.

For example:

if( temp > 10 ) {
    fan = 1 ;
} else {
    fan = 0 ;
}

Expression

An expression can be a single item or a combination of expressions.

Constants, for example:

10
12345

Variables, for example:

temp
fan

Operator expressions are formed as:

<expression> <operator> <expression>

For example, arithmetic expressions:

a + z
b / c
d * e
f - g

Boolean expressions:

a < 10
b < c
c > d
e == f
e <= f
e >= f

Assignment

A assignment consists of a left part and a right part combined with an '=' (equal) sign. The left part should always be a variable reference. The right part is an expression.

<variable> = <expression> ;

For example:

temp = temp2 - 10 ;

Screens

Screens is a way to define your screens.

Screens are presented as pages.

Changing pages can be by user control, or program control, or both.

Only 1 page at a time is shown.

Settings page

Settings is a predefined page to edit settings.

Screen page

A normal screenpage consists of labels and fields.

Labels are fixed texts

Fields are dynamic texts, presenting values from variables.

A screenpage is divided in a grid. The origin of the grid is top-left. The grid starts counting with 0,0.

Telemetry

Telemetry is the process of transmitting data from a device to a remote system for monitoring and analysis.

This is useful for monitoring, saving sensor values in a database, make graphs, and many more applications.

Telemetry routing

Here you specify which transport to use for the telemetry.

• Serial
• MQTT

Telemetry var mapping

This is the folder containing the "Reporting field" items. These specify which variable to send.

Reporting field

To add a value to the data stream, enter the name of the variable (this can be a sensor that you have defined in the Hardware folder) and the tag that you want to assign to it.

The tag is a numeric value, you choose, to give an unique id to the value in the case when the transport mechanism is not able to send texts.

Temperature sensors TMP35, TMP36 and TMP37

The TMP36 (and TMP35 and TMP37) is a low-cost, precision temperature sensor that can be used to measure the temperature of a wide range of objects or environments. They output an analog voltage signal that is proportional to the temperature (in Celsius) being measured. This makes them very easy to work with.

Connect one to an analog input pin (see: Analog input, and the value (between 0 and 1024) read from the pin can be converted to Celcius by this formula:

( ( sensor_value / 1024 * Vcc_in_millivolts) - offset_value_in_millivolts )
/ scaling_factor

Take the offset_value_in_millivolts and scaling_factor from the table below.

For example, for a TMP36, 5V Vcc it would be as follows:

( ( sensor_value / 1024 * 5000) - 500 ) / 10

Which can be simplified as:

( sensor_value * 500 / 1024 ) - 50

Or even:

( sensor_value * 49 - 5026 ) / 100

You can check the math using the reference mV at 25C.

The use of Floating-Point Values in Embedded Applications

Recommendation

If you decide to use floating-point values in your embedded application, ensure that you understand the implications and potential pitfalls. Consider using fixed-point arithmetic or integer operations wherever possible to maintain accuracy, performance, and reliability. Always test thoroughly in real-world scenarios to ensure system stability and correctness.

WARNING! Dangers ahead!

Precision Limitations

Floating-point numbers have inherent precision limitations. Small rounding errors can accumulate over time, leading to significant inaccuracies in calculations.

Performance Overhead

Floating-point operations, especially on microcontrollers without a dedicated floating-point unit (FPU), can be significantly slower than integer operations. This can lead to performance bottlenecks in time-critical applications.

Memory Consumption

Floating-point variables typically consume more memory than their integer counterparts. This can be a concern in embedded systems with limited memory resources.

Non-deterministic Behavior

Due to the imprecise nature of floating-point arithmetic, results can sometimes be non-deterministic, especially when comparing values for equality.

Complexity in Error Handling

Handling errors or exceptions related to floating-point operations (like underflow, overflow, or division by zero) can add complexity to your code.

Portability Issues

Different microcontrollers or compilers might implement floating-point arithmetic differently, leading to inconsistencies when porting code between platforms.

Power Consumption

Floating-point operations can consume more power, which might be a concern for battery-operated devices.

Limited Support

Some low-end microcontrollers might not support floating-point operations at all, or they might require additional libraries to emulate such operations.

Debugging Challenges

Debugging floating-point issues, especially rounding errors, can be challenging and time-consuming.

Safety and Reliability

For safety-critical applications, the use of floating-point can introduce uncertainties that might be unacceptable. It's essential to thoroughly test and validate any system that relies on floating-point calculations.

Troubleshoot mac installation

Mac security fixes

Apple's security requirements are all good and well, but it is quite cumbersome to satisfy all of them, so we gave up on that.

You'll have to jump through an extra hoop to install Bendyroad software.

Open the downloaded files folder in Finder.

Right-click on brainbuilder-[version].pkg, and choose menu item Open with [Installer].

At this point, a warning pops up.

Click on [Open]

Troubleshoot windows installation

Microsoft security fixes

We have given up on attempting to satisfy all the complex and ever-changing Windows security requirements, so Windows will issue a warning when you install Bendyroad software.

Most browsers do not allow double-clicking on a downloaded file. You have to navigate to the location where downloaded files are stored, and then double-click on it.

Once you start the installer package, Windows Defender shows up with a warning.

Click on [More info]. The name and version of the package are displayed as: brainbuilder-[version].msi.

Click on [Run anyway]. The installer will start.

Types

Each of these data types serves a specific purpose and can be used to optimize memory usage and computational performance in your system.

Bits

A BIT represents a binary digit, which is the smallest unit of data in a computer system. It can hold one of two values.

Integer

"Signed" means it can represent both positive and negative values.

"Unsigned" means it can only represent non-negative whole numbers.

Floating

Floating point numbers are designed to represent real numbers, allowing for a wide range of values with varying degrees of precision. The range and precision of these numbers depends on the specific implementation.

See also: The use of Floating-Point Values in Embedded Applications.