View Full Version : ADC or Controller Switch Over

02-27-2005, 08:19 PM
Hi All

Im a newbie on this forum...Im a student at Delhi College of Engineering, 2nd year, ECE...Im a robotics enthusiast n hobbiest...I've taken up a small workshop on microcontrollers and have made a start...a line follower robot...obviously with the help of this site, of course...now i want to make my next project involving ADC's...but i have some quiries...
(1) Are ADC's costly here in India...
(2) Im currently working with AT89C51/51 uC's. I know that the PIC controllers have some analog ports whic greatly simplify the interfacing using them. However um confused whether to switch over at an early stage...Im a newbie, just an experience of 3 months...

Please help me all...Thanks n hoping for a nice journey ahead with you all...


02-28-2005, 10:24 AM
A simple parallel ADC is the ADC0808 [8 bit]...
Its within 100Rs..
However working with an onboard ADC on a uc makes wiring and programming easier...

an external parallel ADC-needs 8 data lines,3 control lines
an external seral ADC-needs only 3 lines.DATA,CLOCK and chipselect
an onboard ADC-needs only an analog in

Try using a parallel ADC first,ul get the hang of terms ,like Vref and stuff..u can even wire the ADC without a Uc

Serial ADCs need programming,but only 3-4 lines of assembly

Onboard ADCs just need to be initiallised an read from
an eg in pic basic pro
ADCIN 0,adcval
[which means select analog channel 0 of the UC,and put the valuein adcval variable]


02-28-2005, 04:33 PM

I dont recommend a seprate ADC ( unless u require very high resolution ) Insted go for the ones built inside the uC's they are quite good 8 pins of 10 bit resolution in Atmel mega 8 ( mega 8 costs 200 bucks ) .

Simple to use and program will make life much easier

02-28-2005, 06:19 PM

if you do use an ext. ADC ...try ADC 0804...costs around Rs 90 to Rs 120...single channel ,8 bit no frills...yet very versitile.....& no probs. in operation

02-28-2005, 10:02 PM
Thank you all for the reply(s). I was thinking of going for onboard ADC's...Now that vikas has mentioned about ATMEL mega 8, i would want to know where i can get it in Delhi...I have a programmer board for AT89Cxx series...so will mega 8 get programmed in it...or i would have to get a programmer as well...yet more thing that i heard that PIC programmers are cheaper to build...so please tell me which one would be a more economical solution...
(1) Hold on with ATMEL...
(2) Switch over to PIC...

Thank you...

03-02-2005, 08:46 PM
Hi all...
I don't understand where two of my posts went???...
neways um writing again...
Hey Vikas mentioned bout those ATmega8...i heard they're quite easily available in delhi...now i want to know the big thing...how to program it...
pls tell me about programming this chip and some free softwares to program it in C/C++...I don't know assembly...


03-03-2005, 12:01 AM
For the PIC

Assembly : MPLAB/MPASM
Basic :PICbasic/Picbasic pro

03-03-2005, 12:34 AM
A real good compiler for almost all microcontrollers is sdcc ( Small device C Compiler), by Sandeep Dutta , u can find it on sdcc.sf.net ( Support for linux available, it is really intersting , it has really a lot of packages included in it , including simulator, assembler, etc)

Then for PIC

use the the MicroChip software on windoZZZ
and for linux compilers : use pplin etc
for debian use the debian pic micro packages

for AVR use
use avr-gcc and avrlib and use sp12 to download it.

If you want some tutorials on Microcontroller hacking ( Linux) get the latest Linux for you or otherwise go to pramode.net

03-03-2005, 12:39 AM
I had recently seen a real cool sites for , site of wichit Sirichote http://chaokhun.kmitl.ac.th/~kswichit/

All of you check this out

03-03-2005, 01:22 AM

Im an avr fan so i stick with AVR :) .. So here is the advantage if you go in for AVR

- MAny C compilers ( Many Free and paid ) Try winavr it really good .
- Huge community support ( very large no of routines and snippets availible off the shelf .
- Powrfull uC unlike PIC and x51 avr is RISC ( 1 inst / cycle ) So in some apps it is the only sol
- Cheap and availible easily
- Easy programming ( unlike pic and x51 which require strange voltages ) with lots of free tools ( basic progammer can be built for Rs 20 -25 )

Hope this helps

03-03-2005, 09:16 PM
Hi all

Thanks for all that....still soem more questions...

(1)I'm using sdcc...can i program for AVR in it...i guess ATmega8's really good for me...

(2)Please tel me bout some links for the programmers for ATmega8...circuits that work...and it would be great if someone has already tried them...

(3)Softwares to program this ATmega8....

One more thing i wnated to ask...Are anyone workign on neural netwrorks and their applications in robotics...I wanted to learn this neural netwoks...if someone could help me out...thanks guys...