Embedded Software Systems and Basics By John Pereless
Embedded software is system based software, programmed to control operations under a specific machine or mechanism or devices that are not typically function or thought of as computers i.e. devices those operates on certain fixed sets of operations and deliver some stand by solutions as an outcome. It is typically specialized & embed for the particular hardware that it runs on and has a time as well as memory restrictions. This term embedded is often used in exchange of firmware [a software or program that coded on a memory device], though firmware can also be applied to read only memory i.e. ROM based code on a computer [The first booting of your PC], on top of which the operating system executes, while the embedded software is technically the only software on the device in queue.
A short and stable functional specification is that no or not all operations of embedded software are controlled via a human interaction, but through machine communication mode instead. A machine runs the software through some set of so called predefined buttons and operations in the installed or embedded system.
Product manufacturer installs/fixes embedded software in the available resource or modes of facilities i.e. electronic mechanisms in cars, printers, telephone systems, modems & other wireless devices such as routers, ports etc , robots, appliances, kids toys & further gaming devices , security alarms systems, medical equipments such as a cardiac pacemakers, entertainment media i.e. televisions and set-top boxes, and digital watches etc. The operations performed by these well written programs or software can be very simple, like procedure control, energy control, lighting controls running on an 8 or 16-bit microprocessor and a few kilobytes. Megabytes of memory or can become way sophisticated in applications such as aviation by airplanes, defence by missiles, and further operation control systems.
How embedded software are different than Application software
Many customers are aware from application software which are developed for accomplishing some tasks within the system or computer processor based systems. They provide specific functional utility in a computer system. There exists a minor yet countable difference that embedded software however is not visible, but not less complicated too. In case of application software, embedded software uses fixed or we can say dedicated hardware and capabilities and they must use the built in or installed memory/processor in operations. Further we can say, they are restricted in using third party procedure call for accomplishment of further system resources in exchanging the functions rapidly as we can see in a computer system which often uses the network resources too in case of requirements. In further explanation, we can say that an embedded system or software is a static available resource that fulfils the unique and pre-defined functional demand while an application software further adds features and utility to an existing computing system.
In addition, embedded software needs to be included all required drivers at manufacturing or installation/integration time, and these drivers are written for the specific hardware at that point of time.
Memory accessed by these systems is also different i.e. an embedded system or software accesses memory from the available limit through its DMA based USB or SPI or Serial Ports protocol i.e. Direct Memory Access while in computer based application software, memory requirement is adjusted dynamically at run time and there are so many protocols exists for that and the most commonly known mechanism is Swapping of pages at run time while virtual memory need adjusted as per the run time on demand memory needs.
The memory & processing resource requirement vary as per the type of system chose. The programming used to code the program can be C, C++, Java or advanced level application programming depending upon the complexity of the system features as well as its operation.
