Comments on: RS232 Communication – The Basics

By: Ahmed

Ahmed — Thu, 19 Aug 2010 05:19:37 +0000

thanks a lot , really good and simple tutorial . i am starting with AVR , and i am glad that found your tutorial that soon ,

keep on!!!!

By: Caio

Caio — Thu, 05 Aug 2010 14:08:23 +0000

Wow! Your tutorial is very good! Thank you so much for making me understand! Yeah! Yipee!

By: bhavin

bhavin — Sat, 10 Jul 2010 16:39:08 +0000

your tutorials are good and have helped me a lot

By: Aditya

Aditya — Fri, 09 Jul 2010 15:16:58 +0000

gud tutorial..
it really interesting….

By: Avinash

Avinash — Fri, 09 Jul 2010 07:08:41 +0000

@Abhishek
The NEXT Tutorial is here

http://extremeelectronics.co.in/avr-tutorials/rs232-communication-the-level-conversion/
http://extremeelectronics.co.in/avr-tutorials/using-the-usart-of-avr-microcontrollers/
http://extremeelectronics.co.in/avr-tutorials/using-the-usart-of-avr-microcontrollers-reading-and-writing-data/

By: Abhishek

Abhishek — Tue, 06 Jul 2010 16:44:45 +0000

where is the next tutorial?

By: Sameer

Sameer — Tue, 25 May 2010 08:55:46 +0000

Hi Avinash,

If receiver is not ready and there is no handshaking, how transmitter and received can be synchronized? Receiver could be ready at any point during data bits also and can treat any low level as Start bit and thus will always read wrong data. Any idea about how to synchronize such a system without handshaking?

Regards,
Sameer

By: RS232 Communication using PIC18F4520's USART - PIC Microcontroller Tutorial | eXtreme Electronics

Tue, 11 May 2010 04:14:38 +0000

[...] RS232 Communication Basics [...]

By: Sunil

Sunil — Tue, 13 Apr 2010 05:21:57 +0000

Hi Avinash,

If you have any basic information on RS485, can you please post it.

Regards,

Sunil

By: xxgeneral

xxgeneral — Thu, 08 Apr 2010 08:49:58 +0000

hi, may i ask u a question?
if following condition is satisfied,
start bit =0;
stop bit =1;
data bits=8;
no parity;
then rs232 may encounter some problems, when transmitting 10101010 followed by 10101111 as below.
0,10101010,1,0,10101111,1,…

Assume that rs232 missed start bit of “0,10101010,1″,then it will start at next “0″.It’s 101010,1,0,1.Now, rs232 will receive a wrong number but without error report.

How to resolve this kind of problems?Does it mean that rs232 is not so much reliabel?

Thanks a lot!

Regardly
xxgeneral
2010-04-08

By: Sunil

Sunil — Thu, 01 Apr 2010 07:50:03 +0000

Hi Avinash,

Thanks for the excellent information of RS232 basics.
It is really Awesome !!!!!!!
If one goes through this tutorial, then the he will never be in need to refer sometime later again on this protocol. It gets embedded permanently in the brains.

Thanks

Sunil

By: Abhishek

Abhishek — Sat, 27 Mar 2010 07:50:07 +0000

Thanks a lot dear…
Such a gr8 tutorial!!!

By: Avinash

Avinash — Thu, 04 Mar 2010 03:43:53 +0000

@Kamran Where it is written ???

“baudrate=25; when baudrate is 2400″

By: kamran

kamran — Wed, 03 Mar 2010 19:30:58 +0000

sir, thanx 4 all the info u provided……very useful…..
my ques is that wat does this mean….
baudrate=25; when baudrate is 2400….
wat hav to b writtten for 9600…. and by which criteria…
regards

By: Jon

Jon — Thu, 11 Feb 2010 06:30:54 +0000

Dude! Thanks for this website! I love avr’s and your website and tutorials has helped me tonnes!!!!!!!!!!

Keep it up!!!

By: Bruce

Bruce — Thu, 11 Feb 2010 05:29:44 +0000

Thanks for that excellent info. i never understood this comms protocol until now.

By: Gaurav Parida

Gaurav Parida — Tue, 26 Jan 2010 12:49:16 +0000

there is a minor error i found in the article is that in the reception example
Quote
“When it gets start bit it waits for half bit time i.e. 104/2 = 51uS now it is in middle of start bit it reads it again to make sure it is a valid start bit not a spike.”

well i m pretty sure that 104/2 is 52 and not 51.
the explanation of the articles are just aweinspiring(awesome+inspiring)and gr8 for beginners in the field of robotics and electronics.
Lastly,Thank you for your contribution.

Regards,
Gaurav Parida

By: sumit

sumit — Mon, 11 Jan 2010 08:32:22 +0000

Hi! frnds,
I have 3+ exp. in embedded domain and I have done lots of communication protocol base projects. I think this documents really gives you better gudeline. I am greatful to gives a thanx to technical person who Involved such great kind of activity.

Thanx & Regards
Sumit Gupta

By: vikram

vikram — Tue, 01 Dec 2009 09:59:30 +0000

Avinashji , hats off for u.
i hav done b.tech. but this type of explain i havenot seen anywhere. may this site live long life

By: Probal

Probal — Thu, 19 Nov 2009 20:11:32 +0000

Thank you so much…really interesting