5.2.5 Embedded Systems

Introduction

The textbook explains that Embedded Systems are small electronic devices which are a combination of hardware and firmware. Firmware is software that is permanently installed in a device or electronic machine. Embedded systems have a microcontroller or a microprocessor that controls the operation of the embedded system through firmware. An embedded system is designed to perform a specific task. In simple words, an embedded system is a small computer built into a larger device to perform a specific function. It is not a general-

purpose computer like a laptop or desktop. It is designed to do one job and do it well.

Definition

Embedded Systems are small electronic devices which are a combination of hardware and firmware. They have a microcontroller or microprocessor that controls the operation of the embedded system through firmware. They are designed to perform a specific task.

Main Idea

The main idea is that embedded systems are the "brains" inside IoT devices. They control how devices operate, process data from sensors, and communicate with other devices. Without embedded systems, IoT devices would not be able to function.

Core Concept

What is an Embedded System? An embedded system is a combination of: Hardware – The physical components (microcontroller , memory, input/output interfaces)1. Firmware – Software permanently installed in the device2. Key Components: Microcontroller or Microprocessor – The processing unit Memory – For storing firmware and data Input/Output Interfaces – For connecting to sensors and actuators Power Supply – For providing energy What is Firmware? Firmware is software that is permanently installed in a device or electronic machine. Key Characteristics:

It is stored in read-only memory (ROM) or flash memory It is not easily changed by users It provides low-level control of the device's hardware It is essential for the device to function Examples of Firmware: BIOS in computers Firmware in smart TVs Firmware in washing machines Firmware in IoT devices Microcontroller vs. Microprocessor Microcontroller: A complete computer on a single chip Includes CPU, memory, and input/output interfaces Used in embedded systems Lower cost, lower power consumption Examples: Arduino, PIC, AVR Microprocessor: A CPU on a single chip Requires external memory and input/output interfaces Used in general-purpose computers Higher cost, higher power consumption Examples: Intel Core, AMD Ryzen In Embedded Systems: Most embedded systems use microcontrollers because they are:

Smaller Cheaper More power-efficient Self-contained

Detailed Explanation

Characteristics of Embedded Systems 1. Specific Task: Embedded systems are designed to perform a specific task. They are not general-purpose computers. Example: A smart thermostat's embedded system controls temperature. It does not do word processing or browse the internet. 2. Real-Time Operation: Many embedded systems must respond to inputs within a specific time frame. Example: An airbag system must deploy within milliseconds of a crash. 3. Resource Constraints: Embedded systems often have limited: Memory Processing power Battery life Network bandwidth 4. Reliability:

Embedded systems must work reliably for long periods. Example: A medical device must work continuously without failure. 5. Small Size: Embedded systems are small and can fit into various devices. 6. Low Power Consumption: Many embedded systems run on batteries and need to last for months or years. Applications of Embedded Systems The textbook lists several applications: 1. Medical Equipment: Heart rate monitors Infusion pumps MRI machines Pacemakers 2. Home Appliances: Washing machines Refrigerators Microwave ovens Air conditioners Smart TVs 3. Point-of-Sale Terminals:

Cash registers Card readers Self-checkout machines 4. Vending Machines: Automated vending Payment processing Inventory management 5. Ticket Scanners: Public transport Event entry Parking systems 6. Automotive Devices: Engine control units Anti-lock braking systems (ABS) Airbag systems GPS navigation 7. Industrial Equipment: Programmable logic controllers (PLCs) Robotics Assembly lines Quality control systems Embedded Systems in IoT The textbook explains that embedded systems help in implementing various IoT solutions.

How They Work in IoT: Data Collection:1. Embedded systems collect data from sensors. Data Processing:2. They process data locally (edge computing) or send it to the cloud. Communication:3. They use communication protocols to send and receive data. Control:4. They control actuators (motors, valves, switches) based on commands. Monitoring:5. They continuously monitor the device's status and report anomalies. Example from Textbook: Embedded systems can monitor a room's temperature and automatically adjust the thermostat. How it works: Temperature sensor collects data.1. Embedded system processes the data.2. If temperature is too low, embedded system turns on the heater .3. If temperature is too high, it turns on the air conditioner .4. It continuously monitors and adjusts.5.

Intermediate Level

In a smart home, embedded systems are in every device. Example: Smart Thermostat Embedded System Components: Microcontroller (processes data) Firmware (controls operation) Temperature sensor (reads temperature) Wi-Fi module (communicates with cloud) Display (shows temperature) Relay (controls heating/cooling) How It Works:

Sensor reads temperature.1. Microcontroller processes data.2. Firmware decides if heating/cooling is needed.3. Wi-Fi module sends data to cloud.4. Cloud sends commands (if needed).5. Relay turns heating/cooling on or off.6. Display shows current status.7.

Important Points

• Embedded Systems = small electronic devices.1.
• They are a combination of hardware and firmware.2.
• Firmware = software permanently installed in a device.3.
• They have a microcontroller or microprocessor .4.
• They are designed to perform a specific task.5.
• Applications: Medical equipment, home appliances, point-of-sale terminals, vending machines, ticket scanners, automotive 6.
• devices, industrial equipment.
• In IoT: They monitor , process, communicate, and control.7.
• Example: Embedded system monitors room temperature and adjusts thermostat.8.
• Figure 5.6 shows examples of embedded systems.9.

Remember

• Embedded Systems = small electronic devices
• Combination of: Hardware + Firmware
• Firmware = software permanently installed
• Components: Microcontroller/microprocessor , memory, IO interfaces
• Designed for: Specific task
• Applications: Medical, home appliances, POS, vending, tickets, automotive, industrial
• In IoT: Monitor , process, communicate, control
• Example: Smart thermostat
• Figure 5.6 = examples of embedded systems
• Characteristics: Specific task, real-time, resource-constrained, reliable, small, low power

Common Mistakes

• Confusing embedded systems with general computers – Embedded systems perform specific tasks.1.
• Thinking firmware is the same as software – Firmware is permanently installed; software can be changed.2.
• Ignoring resource constraints – Embedded systems have limited memory, power , and processing.3.
• Underestimating reliability needs – Embedded systems must work reliably for long periods.4.
• Forgetting about real-time requirements – Some embedded systems must respond within strict time limits.5.
• Assuming all embedded systems are the same – They vary widely in complexity and capability.6.
• Overlooking security – Embedded systems need security to prevent attacks.7.

Quick Revision

Embedded systems are small electronic devices that are a combination of hardware and firmware. Firmware is software permanently installed in a device. Embedded systems have a microcontroller or microprocessor that controls operations through firmware. They are designed to perform a specific task. Applications include medical equipment, home appliances, point-of-sale terminals, vending machines, ticket scanners, automotive devices, and industrial equipment. In IoT, embedded systems collect data from sensors, process it, communicate with other devices, and control actuators. The textbook example is an embedded system that monitors room temperature and automatically adjusts the thermostat. Figure 5.6 shows examples of embedded systems.

60-Second Revision

Embedded Systems = small electronic devices Combination of: Hardware + Firmware Firmware = software permanently installed Components: Microcontroller/microprocessor , memory, IO Designed for: Specific task Applications: Medical, home appliances, POS, vending, tickets, automotive, industrial In IoT: Monitor , process, communicate, control Example: Smart thermostat Figure 5.6 = examples of embedded systems Warning: Embedded systems have resource constraints