Chapter 12 - Electronic Systems Processing

In what configuration do most input components, especially sensors, work best in an electronic system?

Most input components work best in a potential divider.

What is the purpose of connecting an input component to both the positive and negative of the power supply?

It helps to provide a consistent signal to an input pin.

What component is used to pull-up or pull-down an input pin to prevent it from floating?

A resistor is used to avoid an input pin floating, which can cause erratic errors.

What type of signal do analogue components produce?

Analogue components give out varying signals.

What circuit is used to provide a desired voltage in response to changing environmental conditions for an analogue input?

A potential divider is used to provide the desired voltage.

In a dark detector circuit, what component allows the sensitivity of the device to be adjusted?

A variable resistor allows the sensitivity to be adjusted.

Why might some output components require a transducer driver?

They require more power than the processing components in the circuit can provide.

What is the function of a transducer driver in a circuit?

Transducer drivers are used to increase the power available to an output component.

Name two types of transistors that can be used as transducer drivers.

A Darlington pair or field-effect transistors (FETs).

What type of component can be used to operate a high-powered circuit with a low-powered trigger?

A relay.

What is a microcontroller?

A component used to control outputs by processing inputs.

What is meant by programmable?

The ability to provide a set of instructions to complete certain tasks.

What is a flowchart?

A simple diagram using symbols to show the steps in a task.

What are the three basic features of a control system?

Input, process and output.

A microcontroller is a computer chip that contains a processor, memory, and what else?

It also contains inputs and outputs.

What do microcontrollers provide to products and systems?

They provide functionality and give intelligence to products and systems.

What is the role of a process device in a system?

It takes the signal from the input stage and acts on it by changing it in some way.

Give an example of how a process device might act on an input signal.

It might introduce a time delay, count events, or make decisions.

A microcontroller is an example of a single board computer (SBC) and is manufactured as an _________ ________ __

integrated circuit (IC)

What does PIC stand for in the context of microcontrollers?

Peripheral Interface Controller.

What is the state of a PIC microcontroller when it is first manufactured?

PIC microcontrollers are empty when manufactured.

Can PIC microcontrollers generally be reprogrammed after a program is uploaded and stored on them?

No, PICs generally cannot be reprogrammed.

Name three examples of small, reprogrammable microcontrollers.

Micro:bit, Raspberry Pi and Arduino.

What is a key advantage of reprogrammable microcontrollers like the Micro:bit?

They can be reprogrammed by erasing their instructions to be reused in different systems.

What is a major advantage of using microcontrollers regarding the physical size of a circuit?

The size of a circuit can be significantly reduced because programming replaces physical components.

What is a disadvantage of using microcontrollers compared to traditional integrated circuits for simple systems?

They often cost more and are therefore not always the best option for simple systems.

What is a disadvantage of using microcontrollers related to equipment and cost?

Programming software and hardware is required, which can be expensive to buy.

Name a text-based programming language used for microcontrollers.

Python, BASIC or C++.

Name a type of programming that uses visual elements rather than text-based commands.

Block-based programming.

What is the main advantage of text-based programming languages?

They add more flexibility.

What is the main disadvantage of block-based programming editors?

They can be limiting if complex programs need to be written.

What shape is used to represent a decision in a flowchart?

A diamond shape.

What shape is used to represent a process in a flowchart?

A rectangle.

What shape is used for the start or end of a flowchart, known as a terminator?

A rounded rectangle or oval.

What shape is used to represent an input or output in a flowchart?

A parallelogram.

In a flowchart, what is it called when the options from a decision feedback into the system?

This is known as a feedback loop.

What does CAD stand for in the context of testing electronic systems?

Computer-Aided Design.

What is an advantage of testing a control system virtually using software like Tinkercad?

It is less expensive and quicker than physically building the system.

In the Micro:bit example, the green, amber, and red LEDs are all connected to which common pin?

They are all connected to the ground pin (negative power).

Some electronic components are 'polarised'. What does this mean?

It means they must be placed in the circuit the correct way round.

In the pelican crossing program, what does setting a digital write pin to 'HIGH' mean?

It means the component connected to that pin is turned on.

In the pelican crossing program, what does setting a digital write pin to 'LOW' mean?

It means the component connected to that pin is turned off.

What is the purpose of the 'wait 1 second' block in the Tinkercad program?

It creates a one-second pause or delay in the program sequence.#

How is the flashing amber light achieved in the block-based program?

A repeat routine is used which turns the amber pin (Pin 1) on and off multiple times.#

What can be used on the Micro:bit itself to show pedestrian signals like a cross or an arrow?

The built-in LEDs on the Micro:bit can be used.#

The process of writing computer software for a microcontroller is called _

programming#

What is meant by 'in-circuit programming'?

The microcontroller is programmed without being removed from the circuit.

If a system does not support in-circuit programming, what must be done to program the chip?

The chip must be taken from the circuit and placed in a special downloader.

What type of cable is commonly used to download a program from a computer onto a microcontroller?

A serial or USB cable.

In the pelican crossing traffic light sequence, what is the first step?

A pedestrian pushes the control button to activate the traffic signals.

After the red traffic light, what signal is shown to pedestrians to indicate they can cross?

A green pedestrian light.

What happens to the pedestrian light when the traffic light is a flashing amber?

The pedestrian light is a flashing green.

What is the learning outcome stated in the 'Programmable systems' slidedeck?

I can use a microcontroller to design and test a control system.