Comments on Design with Microcontrollers: Interfacing RTC & serial EEPROM using i2c bus, wit...

hey guyz iam ssebabi godfrey, can u pliz get the ...

2012-02-05T07:11:11.784-08:00

hey guyz iam ssebabi godfrey,
can u pliz get the full c code for interfacing PIR sensor with MCU atmega128 avr

hi dharmani sir, this eeprom function is used only...

2012-01-31T05:03:18.649-08:00

hi dharmani sir, this eeprom function is used only one eeprom (24c256). but i want connect 4 eeprom. how to write coding sir, eeprom has four difference address modes, so how to select purticular address of eeprom and write sir, please help me

Hello Sir,i am working on project where I am using...

2012-01-18T03:08:55.423-08:00

Hello Sir,i am working on project where I am using RTC 1307 and EPROM 24c04 to display time and when interrupt come, controller should capture that time and save it on eprom memory.Would you please tell me the c code for it.I am working with AT89C51 controller.

can u please post one sample program for analog co...

2011-11-23T09:25:23.540-08:00

can u please post one sample program for analog comparator using atmega162.

hlo dharmani. I am building a room scanner bot usi...

2011-11-23T08:11:52.304-08:00

hlo dharmani.
I am building a room scanner bot using atmega16 and want to interface rtc and eeprom as you did. Kindly send me the complete description on mani2246@gmail.com it will help me a lot

Hi Dharmani, Quick question, the erase function d...

2011-09-25T11:15:25.990-07:00

Hi Dharmani,
Quick question, the erase function does not work for me, any idea if I should be adding the repeat start ondition in the for loop, cause as per the simulation in ISIS only the first page i.e page 0 seems to get erased. All other pages stay intact even after erase.

hello sir,i am a beginner in Embeddedsystem.can u ...

2011-02-21T02:18:55.154-08:00

hello sir,i am a beginner in Embeddedsystem.can u send me notes on Embedded C and how to write sourcecode for a task.my id is punit05.namdeo@gmail.com

please help me on how to interface micro SD card t...

2011-02-14T02:46:43.367-08:00

please help me on how to interface micro SD card to ATMEGA8535..kindly please let me know..:)

Check out my post on microSD card interface with A...

2011-01-24T04:35:28.625-08:00

Check out my post on microSD card interface with AVR:
http://www.dharmanitech.com/2009/01/sd-card-interfacing-with-atmega8-fat32.html

Hi Dharmani sir,this is Mithilesh. we are working ...

2011-01-24T03:28:20.630-08:00

Hi Dharmani sir,this is Mithilesh. we are working on a project,data logger into micro sd card , but we are facing problem with interfacing it with microcontroller.Can you please help us out..my email id is mithilesh1dhupia@gmail.com

hi dharmani, Can you give examples of programs wit...

2010-07-17T17:14:57.075-07:00

hi dharmani, Can you give examples of programs with codevision. The same with your schematic. this is email(amin3vdc@gmail.com)

Hi Dharmani, this is kumar. from past week we tyin...

2010-07-15T02:32:22.252-07:00

Hi Dharmani, this is kumar. from past week we tying to interface ds1307 with atmega32 we have tried al the codes ...but can't.so please help us

Hello My name is John and I am trying to store an...

2010-04-29T01:32:51.369-07:00

Hello

My name is John and I am trying to store and then display nmea strings from a gps using the mega324p with an i2c eeprom.

I have managed to write all the nmea strings to the eeprom, my problem is now to try and read and display them in Hyper Terminal.

At the moment in my circuit simulator I am able to see the data being stored, but when I try and read the data that has been stored it does not go the eeprom addres I was expecting.

I am using a RS232 conection to the pc.

Here is the c code:

#define EEPROM_RD 0xA1
#define EEPROM_WR 0xA0

TWI_Start();
TWI_Write(EEPROM_WR); // write command
TWI_Write(0x00); //MSB
TWI_Write(0x01); //LSB
TWI_Start();
TWI_Write(EEPROM_RD); // read command
// TWI_Write(0x00); // Address what I

TWI_Read();

TWI_Stop();

/*Functions for write and read from the EEPROM*/

void TWI_Start(void)
{
TWCR = 1<< TWINT|1<<TWSTA|1<<TWEN;// repeated start condition
while(!(TWCR & 1<<TWINT));
}

void TWI_Write(uint8_t data)
{

TWDR = data;
TWCR = 1<< TWINT|1<<TWEN;
while(!(TWCR & 1<<TWINT));

}

void TWI_Stop(void)
{

TWCR = 1<< TWINT|1<<TWSTO|1<<TWEN;
_delay_ms(1);
}

//* TWI Read Function *//

uint8_t TWI_Read(void)
{

// start read transmission
TWCR = 1 << TWINT | 1 << TWEN;
while (!(TWCR & 1 << TWINT));
return(TWDR);// returns the data from the written file.

}
my email address is tuckerj1@aston.ac.uk.

Please feel free to give me some tips.

Many thanks for your time.

John

Hi mr Dharmani and hello from Canada. I find your ...

2010-04-13T06:05:49.317-07:00

Hi mr Dharmani and hello from Canada.
I find your article very usefull and well written, and I am trying right now to port the code to an ATmega 644.
I have changed a few things but it still does not work. I am not completely new to atmega but I am to AVRstudio and I am a bit lost!! can you help me on that one. I understand I have to modify the ports allocation: i2c on port C and rs232 on port D.
Then I went on the project settings, in fact I created a new project with a 644 at 20mhz clock. It compiles with no errors but I get those messages in the message window:
Loaded plugin STK500
Loaded plugin AVR GCC
Loaded partfile: C:\Program Files\Atmel\AVR Tools\PartDescriptionFiles\ATmega128.xml

I am not to sure about the implications of these, can you clarifie this to me.
AVRstudio is truly a great suite but finding my way around is somewhat complicated by the fact that I am completely new to GCC and that sort of things, I whish there was a single for it!
Thanks, Luc

Hello! I send mail to author and repost my trouble...

2010-03-08T13:55:04.442-08:00

Hello! I send mail to author and repost my troubles here
I'm using ATMega16 and AT24C128 EEPROM. Also, I use this datasheet www.atmel.com/atmel/acrobat/doc0670.pdf
First of all I'd want to clarify erasing algorithm. As I see, you use "page write" algorithm to write 0xFF bytes to whole memory. But it's not writing to whole memory, it's write only first page. In datasheet on page 10 quote

If more than 64 data words are
transmitted to the EEPROM, the data word address will “roll over” and previous data will be
overwritten. The address “roll over” during write is from the last byte of the current page to the
first byte of the same page.

I'v write new erasinc procedure, that erasing by pages. If I'm not right - correct me.
Second moment - delay between stop and start conditions. If I try to write two bytes in sequence, MCU hangs up when waiting start condition for second write procedure. But if I make delay between two write procedures, everything is Ok. In datsheet somsing about ACKNOWLEDGE POLLING on page 10 but I don't know how to embed it in your code. But your routines help me great - thank you. Could you help me in my two troubles?

Hi i am working on with the rtc1307 with 8051. Wh...

2009-11-28T09:11:49.538-08:00

Hi i am working on with the rtc1307 with 8051. When i tried entering the time through serial com port through the pc the controller resets again.
I have taken the code from the 1307 datasheet. Plz help
dis is d link of the code

http://www.maxim-ic.com/appnotes.cfm/an_pk/95

and dis is my email:
plz reply

pradeep.mirchandani@gmail.com

hi, this is poonam .i ma working on same project.c...

2009-11-23T22:07:28.266-08:00

hi, this is poonam .i ma working on same project.can you tell me that why eeprom is used with RTC
can you send me details on poonamkothawade@yahoo.co.in

Hi Dharmani sir, I am from jodhpur presently stu...

2009-10-01T01:24:51.092-07:00

Hi Dharmani sir,
I am from jodhpur presently student of MBM Engg college.
I used your rtc interfacing code for atmega8 and it really worked very
good. I am very thankful to you for this help. Sir, I want to share my
further problem regarding to my project please help me.

It uses timer1 in ctc mode at almost 500ms delay. Each time
it flips a volatile uint8_t TIMER_FLAG. An another code in main program
activates whenever TIMER_FLEG is not zero read rtc and display SS/MM/HH
to hyper terminal. This code also flip a LED each time also. It works quite
well.

Along with timer1 It also uses INT1 in falling edge trigger mode. INT1 ISR
disturbs the previous code and bring the compiler out of previous and send
another message to hyper terminal. It also works quite well.

Problem is that sometime (after few minutes or several minutes) all of
sudden LED stops flipping as uC were gone in sleep mode. As soon as INT1 is
applied LED again starts flipping. I have take a number of tests for debuging
but failed to find fault. microcontroller uses internal 8MHz oscillator.
INT1 is applied through a TSOP1738 (Vout of TSOP is connected at pin D3) and
a normal TV remote. It is not using any type of sleeping mode.

//////////////////////////////////////////////////////////
/* I used timer in no prescale mode for pssible removal of
problem so I used LED_cnt to increase delay*/
////////////////////////////////////////////////////
ISR(TIMER1_COMPA_vect)
{ if(LED_cnt>=50)
{
LED_cnt=0;
TIMER_FLAG=1;
}
else
LED_cnt++;
}
////////////////////////////////////////////////////////////
SIGNAL(SIG_INTERRUPT1)
/* signal handler for external interrupt int1 */
{
INT_flag=1;
}
////////////////////////////////////////////////////////////

//////// main program///////////////////////
void main():
{
while(1)
{
while(!INT_flag)
{
if(TIMER_FLAG)
{
TIMER_FLAG=0;
bit_flip(PORTD,1);
....... .
////////////code to send SS/MM/HH to hyper terminal////////////
........
.......
////////////////////////////////////////////////////////////
}
}
uartsendstring("interrupt called");
INT_flag=0;
}
}

Please suggest me some solution to remove this problem.

Hi Rahul, Atmega8535 is having i2c bus (TWI) on-ch...

2009-09-26T00:58:19.314-07:00

Hi Rahul,
Atmega8535 is having i2c bus (TWI) on-chip. Pin22 & 23 are SCL & SDA pins respectively. You can use i2c functions provided in this post.

how to interface i2c to atmega 8535

2009-09-24T03:49:53.115-07:00

how to interface i2c to atmega 8535

please tell me how to interface i2c to atmega 8535...

2009-09-24T03:49:10.470-07:00

please tell me how to interface i2c to atmega 8535 as i didn't find any sda and scl pin in it

Great Article ! Can you please help me change the ...

2009-09-12T07:46:12.094-07:00

Great Article ! Can you please help me change the header files to use atmega32 instead of 1280 . i would be greatful if you can send me modified files to webrains@gmail.com

cheers
sumeet

would you send me the complete project file. i jus...

2009-09-06T14:27:24.765-07:00

would you send me the complete project file. i just want to learn your project, it seem very interesting.
Regards,
Iman
iman_parta_kusuma@yahoo.com

i will wait for your e-mail...thanks

I want to try to implement this RTC and serial EEP...

2009-07-20T20:05:19.661-07:00

I want to try to implement this RTC and serial EEPROM using I2C bus. Could you plaes send me the complete project files (schematics+sources+libs)
Regards,
Althaf
msheikalthaf@yahoo.com

you can reply me on asif164@ohtmail.com

2009-07-16T23:43:33.025-07:00

you can reply me on asif164@ohtmail.com