PIC 16F877 based project help (guidance) :)

[shrinidhi kulkarni]

Hi guys,
i m new to forum... This forum is coolest i have seen.

pls share ur thoughts on this.

i want to design a project where control of environment parameters like temperature , humidity & gases like co2 , o2 is done.

plan i have is... use 16f877 (that has inbuilt ADC) to control the above said parameters.
(i have decide on 16f877, for my plan, after searching net for long days )

Q: Is it OK if i go ahead with 16f877 ?? any other better option?
Also guide me through simulation of design on MPLAB IDE & compiler that can be used ..
thanks in advance

 

[blueroomelectronics]

The 16F877 can do that sort of thing, but IMHO you should figure out what sensors and I/O you require before guessing at which MCU to use.

 

[sunbelt57]

Not everything doable is worth doing. If you just want to get started with the PIC16F877 look for some simple ckts online. If you really want an control/monitoring system like that you might want to consider using a labjack hooked up to your PC. Goto labjack.com and look for the U3 - 16 analog inputs and 20 digital outputs. Very affordable. As far as PIC's go I started playing with the 16F84 about 10 years ago and haven't touched it since. I just started getting back into the 877.

 

[shrinidhi kulkarni]

@sunbelt57----------------------
project im doing is academic. so not going for a module that controls(labjack).

@bill----------------------------
the design will be having 3 inputs from sensors(yet to decide which sensors)... & 3 o/p
o/p are 1. to turn on fan if temp falls below a threshold.
2. to buzz an alarm if co2 level crosses certain level.
3.to buzz another alarm(different from co2 alarm) if humidity is out of set range.
Q: is it OK to use 16f877 for controlling multiple parameters that are concurrently varying???also if any one knows cheap n best sensors for these ..do info

 

[shrinidhi kulkarni]

can u guys give an algorithm to SIMULATE the design in MPLAB SIM..??

 

[bryan1]

shrinidhi kulkarni in that post I just approved you said this was academic, which basically means homework. In your next you demand a finished project so so can hand it in saying it was your idea. Sheesh get a life and go research what chips you need to do what you have been told to do by your teacher. Come back and ask question AFTER you show what you have done and one more demand of asking for a finished project and with one swipe we'll have one less kid demanding we do their homework for them......

 

[ghostman11]

hi i am working on an incubator type project, wich uses ds18s20 tempreture sensors and sht71 humidity sensors. i use the 18f4685 for the mcu, i have no experiance of the 16f chips but i would of thought a 18f would have been a better choice. Like blueroom said your probally better working out the sensors first, to simulate in mplab you would need full code not just simply a algorithm, wich without knowing what sensors your useing just isnt possiable, also for someone to provide full code for the kind of project you require would mean a huge amount of work on there part and just isnt realistic to exspect.
so a quick check list for you.
1, decide what sensors you are going to use by this i mean not just a humidity sensor but WICH humidity sensor, work through the list one by one.

2. Decide what compiler you want to use, do you program in basic, C , or ASM??

3. Decide on the MCU thats most suitable for your needs, its not much good saying a 16f this or 18f that because it has such and such, for example it may have ADC for things like lm335 temp sensors but if you decide to use dallas 1820 sensors then ADC isnt going to be much help, same for the other sensors, some might well be serial or some other protocol.

4. start doing a schematic of the setup.


5. start writeing sections of codes, break your project down into small chunks you can manage.


ah just seen bryans post after i finished typing!! so its homework!!! i hope it dont need to be handed in for a year or two
BTW what exactly do you want to make and when do you exspect to have it finished by?

 

[dhimullai]

hello kulkarni;
better you check this blog... it might be useful to you regarding ADC
Analog To Digital Converter Programming

 

[shrinidhi kulkarni]

yup!! Ur advice is accepted

 

[shrinidhi kulkarni]

Above post was at bryan1 -THE moderator.

@ghostman11 - Thanks a lot for check list . will do it.
**well, i want a prototype of a controller..that controls 3-4 parameters using PIC uc.Have future aim of practically implementing also.
But for academics , within a period of 1 & half month or 2 months have to present the prototype.

 

[ghostman11]

i have to be honest and say that 2 months for that kind of project isnt realistic unless your very very good! i cant speak of the O2 or Co2 sensors as i have never used them, for humidity i used sht71 wich by the way can also do tempreture so that would cut down parts and codeing for you, the bad side is they cost a fair bit.
why not go for light detection humidity and tempreture, it would give you a slightly improved chance of completeing on time. I realy dont want to be negative about your project but your timescale is short and you need to simplify it. do you actualy have to build it or just simulate it?

 

[shrinidhi kulkarni]

hey, thanks a lot..
i just have to show a prototype..that senses parameters and glow some LEDs..indicating that parameters are sensed.

And,wat do you mean by light detection humidity and temperature????
i have studied microcontroller (generics of 8051) as part of acaemics..but new to PIC ( now i am rigorously studying PIC MCU).
guys on electro tech are awesome.. they are doing a great help.

 

[ghostman11]

hi by light detection i mean turns a light (LED) on when its dark and off when its light, you could also have humidity and tempreture sensing. personaly if i was you i would keep it as simple as i could with the time scale you have so use a lm35 temp sensor wich you can just use the ADC with a LDR as part of a resistor devider again going to a ADC and some sort of humidity sensor. it should then be achiveable in your time scale.
if you try and do dallas one wire stuff and oxygen sensors then your not going to have time to do the codeing and its unlikely anyone here even if they were willing to do the code for you would have time

 

[shrinidhi kulkarni]

okie..

will do only..temperature and humidity sensing. also will see if i could use light detection.
thanks man