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In recent time I came across situations where RS485 ports caused lots of problems. The ports basically “burnt down” due to severe EM surges in industrial environment. As a work-around we used to bring in the systems from the site to our repair workshop, repair the device and then re-installed it on the client site. The equipment was expensive and we could not keep many drop-in replacements for that. Then what we did was to add a small hardware which basically translated the RS485 data into TCP/IP over Ethernet. The results were exceptional. This not only completely eliminated the damages due to surges but also reduced the customer annoyance, the logistic and support expanses we faced every time we received a May-day call. So, why should we replace or phase out the RS485 systems with Ethernet:

• Better isolation and hence no burning cases, this reduces cost
• Ethernet is faster
• Ethernet may provide different logical channels on the same physical medium like in one device, I used two TCP ports on same IP. One port for RS485 communication while the other one for digital triggers. This completely eliminated the “muddling” issue of two different data sources while using single physical Ethernet port.
• Much better stack structure in Ethernet as you have lots of options like TCP client, server, HTTP server, SNMP etc. according to requirement.
• Easier and smoother integration with existing TCP/IP-based network like local LAN.

Currently there are low-cost microcontrollers with built-in Ethernet controllers options like those offered by Microchip, TI and many others. This has eroded the myth of cost effectiveness of RS485 over Ethernet. Infact, keeping in view the running cost of both systems, Ethernet is much cheaper than RS485. Therefore, while designing a new system, Ethernet should be preferred over RS485 and if RS485 is already installed, low-cost converters can be used to transport data over Ethernet.

“This industry is all about change. Those that facilitate change will win. Those that resist will suffer”.

Some days ago I was reading an online article. It was about 8-bit microcontroller market, probably some new series launch by a vendor. Above phrase was basically a comment which I loved so much that I decide to write a post about it. It touched my heart, basically!

Embedded systems is all about change. every now and then a new ASIC, microcontroller family, software, development kit etc. is added. A developer like me always wonders what to do and what to leave. There are so many things to do and an engineer’s resources are so small. Time is also an issue and managing time these days is difficult. But one thing is clear, this is the era of “change or die”. If you will change, you will live; if not, you are a dumb; and “dumb one will always die”.

There are some many fields within Embedded Systems, like MCUs, FPGAs, RF, HF, Control systems, Smart Energy, Power Electronics and bla bla with variety of tools to learn. As the time passes by, the need to change oneself rapidly also increases. Well, it’s a tough field, the Embedded Systems. But we have no option but to update ourselves, have we?

Although modern day technologies have now converged practically into embedded systems still there are people among us who still question what an embedded system is?

The field of embedded systems is a unique combination of softwar and hardware where the whole intelligence of the system is confined into the firmware of hardware residing indide hardware itself. Now what is firmware? Firmware is the software or intelligence portion of the systems which resides in the hardware, takes directions from hardware peripherals, processes  information, takes decisions and issues control signals to actuate outputs. The formost effrot in designing embedded systems is to reduce the physical footprint of the system to fit it into the space and weight constrained applications. Another design goal is to keep the cost as low as possible. The advantage of embedding the intelligence into the small hardware is to make efficient and cost effective systems, basically, to make small ordinary things much more smarter than before.

The example of embedded systems are everywhere which we use on daily bases like cell phones, the control in washing machine, tv and tv remote etc. One distinctive difference between general purpose computers and embedded computers is that they are application specific. Also the embedded systens are “all in one” systems based on small computer, peripherals, sensors, indicators, actuators and everything necessary to carryout a specific task, to fulfil a certain objective.

Becuase of their nature, the embedded systems designers must understand both software as well as hardware. only electronics engineer can not design good embeded systems and a software-only guy is incompatible with this field. There are two models of job models followed by companies mainly based on their resources. The large companies have specialist of hardware and software so the engineers need not to design everything. This does not mean that they don’t need to be familiar with each other’s domain as they need to coordinate with each other constantly and regularly. In small companies, the same guy has to do everything. the hardware as well as the firmware (embedded software). Also there are many other things which need to done like casing designs or at least considerable effort in determining the right enclosure of the product and its overall shape.

All in all embedded systems is an interesting field but it is demanding at the same time.