An embedded system acts as a small computer system that has a processor, memory with input and output devices to perform a specific task within a significant electrical or mechanical system. An embedded system affects the real-time decision making of a device being part of the overall mechanism itself.
Generally, modern embedded systems use microcontrollers. And as they perform specific tasks only, engineers can lower the size and cost to improve product performance and reliability. Embedded systems are designed with the same approach as a computer system, still, they perform specific tasks only. Embedded systems most often are only small parts of a larger electrical or mechanical system. Programs for embedded systems are called as firmware and can run with small memory without any screen or keyboard instructions. Here are the main characteristics of the Embedded Hardware Design system.
User Interface
Embedded systems can range from no user interfaces for performing very small tasks to extra large complex graphical user interface(GUI) to manage desktop systems. They use small LEDs, buttons, touch screens, etc., with a simple menu to help users allocate specific tasks to their system.
Processors in Embedded Systems
The embedded process has two broad categories; Ordinary microprocessors (μP) for peripherals and integrated circuits for memory. Microcontrollers (μC) while, on the other hand, on-chip peripherals, hence lower costs, lower size, and reduced power consumption as well. Various microcontrollers are specifically built to perform tasks as per the requirements of embedded systems.
There are also different types of ready-made computer boards available in the market that you can use within embedded systems.
Peripherals
Embedded system use peripherals to connect with any external source that may include
Universal Serial Bus (USB) based devices
Serial Communication Interfaces (SCI) examples are RS-485, Rs-232, RS-422, etc.
Networks such as LonWorks, Ethernet, etc
Analog to Digital and Digital to Analog based
Multimedia cards (Compact Flash, SD cards)
Timers
Discrete IO
Debugging
Synchronous Serial communication interfaces
Tools
In an embedded system, you may find compilers, assemblers, and debuggers. Still, there are many tools to perform particular tasks:
Circuit emulators or debuggers
Digital signal processing
Specific code generating tools
Custom Compilers
Software tools and 3rd party tools
Debugging
Embedded debugging performs at multiple levels based on the requirements and facilities provided. There are many ways of debugging in an embedded system.
Interactive resident debugging such as Forth or Basic present in the shell of the operating system.
External debugging, through a serial port or logging, to trace operations and evaluate on a monitor flash or server.
ICD (In-circuit debugger) represents a hardware device connecting microprocessor with a Nexus or JTAG interface.
ICE (In-circuit emulator) here acts as a simulated equivalent, to manage the functionality of the microprocessor.
Here, an emulator can help in checking the functionality of the hardware design for evaluation, testing, and modification.
Software-only debuggers can work without any hardware modification. Still, they need more precision in control to ensure conversing time and proficient storage space.
As embedded systems are complex in their architecture, the strategy for debugging may vary from one system to another. For high-volume such as mobile phones or portable music players, lowers costs are the primary motto. While for low-volume systems, real-time operating systems are the main focus.
Tracing
Real-time operating systems (ROTS) encourage designers to check and evaluate the performance, timing, and behavior of the system. These ROTS generally supports tracing of all events occurring in any system.
Reliability
Embedded systems can perform the same tasks for years at the same level without any error. And in any case, errors emerge systems correct themselves to the older route. So, embedded systems are more precisely check than personal computers, drives, or switches. Some unique cases may create issues.
· The Systems with no Shutdown time for repairing that includes undersea cables, bore-hole systems, space systems, navigational beacons, etc.
· Systems that should run continuously for particular safety reasons. Such as reactor control systems, train signals, aircraft navigations, funds transfer, and markets.
· Systems might lose clients, destruction of life, or loss of money if shutdown. Such as market making, bridge, and elevator controls, factory controls, telephone switches, and automated services.
Embedded hardware design example includes small MP3 players, wearable electronic devices such as watches, smart specs, etc., to a significant large hybrid vehicle, avionics, medical imagery, traffic light controllers, equipment racks.
