tips developing professiona embedded projects

hii this is my first post.

i am a hobyyist in embedded system for the last 2 years and have done few projects with pic microcntrollers (16f,18f) and ccs compilers.
but now i have move on to develope commercial and industrial embedded projects.

could anybody help me with tips that whatever things are recomended to ensure the stability and performance of the system, espessially if the system run 24x7
????

pls help me
thanks in advance

Here are some of these,

1. Good power supply : A reliable SMPS is a good choice over transformers.
2. Use of soldering flux : NEVER forget this.
3. Use of hot glue : This baby is really helpful to keep those fragile parts safe.
4. Use of spacer nuts : Use plastic/rubber spacer nuts if you use metal case.
5. Glass epoxy boards : Prefer over paper phenolic.
6. Ground plane : Fill empty spaces of copper layer with the ground plane.
7. Switches : A part prone to malfunction. Use good quality ones.
8. Pots and presets : Same here.
9. Tie all the cables : Make sure to separate power and signal cables.
10. Try to incorporate all the things in one package. Avoid interfacing too much parts.

Finally,

Your software Part.
1. Note all the exceptions that may happen and include a code to handle them.
2. Place some status LEDs. This helps to debug the problem.
3. Place an activity LED, like one on the PC.
4. If code is perfect, prefer OTP chips over flash ones.

Hope this helps.

Good Days

thank u very much that was really helpful.

but how is OTP chip programming...

i am currently working on pic 18f platforms.


also how is the usage of external watch dog timers???

i heard that the PLC uses highly reliable micro controllers and circuits like external watchdog timers.

also could u pls tell me what are the drawbacks of micrcontrollers over PLC. because it is used extensively in industries...

some say it is easy to program...
but is that the only reason?????

Hi

OTP (One Chip Programmable) chips come at really cheap price. And they are more durable over conventional flash chips, with the only drawback being its one time programmability.

About PIC controllers, I can't help you much as I work under ARM platforms.

PLCs are easy to program as they come with the softwares which handle most of the coding. You only have to enter your controlling logic in that software. So, it is easy in control applications. and of course, PLCs make use of microcontrollers.

thanku but as per ur reply can i use microcontroller wherever a PLC is used.
provided a better stability test is conducted?

and about OTP chips what are the developing steps like can i code it like normal flash uCs and then export it into OTP?

what sort of Burning equipments are required?

There is no difference between coding of OTP anf flash chips. Same HEX file you can burn in OTP. For example, a HEX file made for 89s52 (Flash memory) can be burned into 8051BH (OTP). Provided the memory capacity specifications are same.

PLC is actually a stepped up version of microcontrollers, created with adding extra peripherals. Those peripherals are mostly relays. Hence if you wish to use microcontroller, ther you also have to build entire circuit. So, I will prefer using ready to use PLCs.