Blocks
Introduction
This is a bit of a dry theoretical explanation, but to get the most out of BrainBuilder, it is helpful to get a general idea of the concepts used. The examples are extremely basic, and not meant to illustrate the entire set of possibilities (they’re endless!).
Blocks
A block is an abstract entity. A block performs a function.
There are several types of blocks:
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Hardware blocks that read from and write to hardware.
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Logic blocks process inputs, rules, and write to outputs.
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Specialized blocks, which have complex functionalities built-in (for handling LCD screens or keyboards)
All blocks can have inputs (also called sources) and outputs.
Variables
In- and outputs communicate via variables. Outputs set variables, inputs read variables.
A block can own variables. When a block is added, a variable, usually with the same name as the block, is automatically created.
For instance, a blinker block named 'myblink1', automatically creates an output variable 'myblink1' that goes high and low on the frequency specified in the 'myblink1' block, and can be used for making a LED blink.
To make 'led1' blink; specify 'myblink1' as the source in 'led1'
A switch named 'sw1' automatically create a variable named 'sw1' that represents the state of the hardware switch. You can use variable 'sw1' to control the state of another variable directly, or use it in a rule.
A block can own input variables.
A LED block called 'led1' automatically creates a variable named 'led1'. By changing the value of variable 'led1', the hardware LED can be turned on or off.
A rule block
To connect a switch 'sw1' to a led 'led1', you write a rule like: "led1 = sw1; "
This links the output of 'sw1' to the input 'led1' via the rule
Derived variables (or expressions) are a special kind of variable to make things easy. A block can follow an expression. In that case it does not have its own input variable(s).