Real time clock ICs

[Eng4444]

Hello,

i'm again search for Real time clock but this time, not for DS1307.

Could anyone provide me with any PicBasic Pro program for any real time clock IC used with any PIC?

i'll just buy both ICs and make my life easier... because i'm about to break my head with this DS1307 and PIC16F876A ...

[sayzer]

http://www.picbasic.co.uk/forum/showthread.php?t=423

[Jerson]

Hello,

i'm again search for Real time clock but this time, not for DS1307.

Could anyone provide me with any PicBasic Pro program for any real time clock IC used with any PIC?

i'll just buy both ICs and make my life easier... because i'm about to break my head with this DS1307 and PIC16F876A ...

This one is for the PCF8583 from Philips. Perhaps you can use this as a starting point to talk to either this device or a DS1307.

' Read the time in BCD format
RTC_GetTime:
I2Cread i2sda, i2scl, $A3, 2, [Second, Minute, Hour]
return

Jerson

[BobK]

Hello Eng444,

What's the problem? This forum has many examples of using RTC's including one back in Oct 2004 by Tonigalea that uses a DS1337. Paul Borgmier (sp? sorry) put 2 really nice RTC programs on this site last year that don't even use a separate RTC chip. I have tried them and they work very nice. They even have an alarm time example in them. I am on my 3rd project now using the DS1337 RTC. I use this as my projects need to keep accurate timing with a battery backup. I have even done routines to handle daylight savings time. I have used this RTC with a 16F88, 16F877A, and a 18F452. They are easy to work with but with everything else in life there is a learning curve. I found it very worth the time I invested.

There are also several examples of elapsed time counters here on this site from Darrel Tayor. Melanie has given us the Olympic Timer based on the 1302 RTC. She also has a clock program posted on the MELabs website.

Your post did not say specifically what your problem is. Some RTC's require converting data from the RTC from BCD to decimal. Paul Borgmier's clocks don't use this conversion. Tonigalea's DS1337 program doesn't use it.

Read through the posts here on this site and try a few things. Let us know more about the problem so we can help you! The people here are great and willing to help!

BobK.

[Eng4444]

I am working on a certain project and do not have any knowledge in RTC, nor how to program them. In fact, i just learned PicBasic Pro...

I have Pic16F876A and i am trying to manage to make my DS1307 work.

I Have read all the examples but as i am new to this thing, i didn't understand them...

i do not need alarms...etc etc i do not need it sophisticated at all. i am to calculate Energie which is given by: Energy = Power * time.

i already got power in a certain variable and now, i need to get the time elapsed in order to multiply by power...

any help?

[BobK]

Hi Eng 4444,

If you aren't looking for a "time stamp" of time and date then what you should try is Darrel Taylor's "Elapsed Timer" program on this site. Your program can control when to start timing and when to stop timing. Melanie's "Olympic Timer" is another example of a start and stop timer. You should look at these two programs. Both of them output the result to an LCD display. Both of these programs use a background timer using the PIC's timers. You can have your PIC do the calculations based on the inputs and then display the results.

The May 2006 issue of Nuts and Volts magazine has a nice tutorial on using PIC timers including a sample program that should help you out understanding how these timers are used. I believe this forum also has numerous posts relating to using PIC timers. I personally am just starting to use them so I wouldn't be much help in the actual design of one at this point. I just have a basic understanding of how they work.

[sayzer]

Also as BobK pointed in right direction, have the followings into consideration.

If you use RTC to calculate the elapsed time, you will have difficulties when time passes from one minute to other, or from one hour to other. You will be lost in HEX conversions to come with elapsed time.

I highly recommend using Melanie’s Olympic timer. It is already a timer just as you need, it is not an RTC.

It is quite easy to implement it into your PIC; even if you can’t use it with your PIC, have your energy calculation in your PIC by getting a signal from a separate PIC in which the Olympic timer is implemented.

[Eng4444]

Hi Eng 4444,

should try is Darrel Taylor's "Elapsed Timer" program on this site. Your program can control when to start timing and when to stop timing. Melanie's "Olympic Timer" is another example of a start and stop timer. You should look at these two programs.

__________________________________________________ ______________

Sorry but where to find those 2 programs on this website? in which section?

[Jumper]

Hi,

If you dont use a backup battery for the 1307 make sure that the un-used leg for the backup function is tied to ground. You can find this in the datasheet but if this is not done the chip will not work properly (sometimes it doesn't, other times it does but never when you want it to).

We are using the 1307 and it is doing fine.


TRIS? = %00000000 ' all pins to output just replace ? with port name

SDA var Port?.? 'define port for I2C communication replace ?.? with pin
SCL var Port?.?

Hours var Byte
Minutes var Byte
Seconds var Byte
RTC var Byte
I2C_Adr_B var byte


RTC = % 11010000 ' Device adress on I2C bus
I2C_Adr_B=0

I2CWRITE SDA,SCL,RTC,I2C_Adr_B,[128,0,0,0,0,0,0,128] 'Reset time to 0 and stopped, 12 hour setting

Start_RTC:
I2C_Adr_B=0
I2CWRITE SDA,SCL,RTC,I2C_Adr_B,[0,0,0,0,0,0,0,16] 'Start RTC if you put a resistor and LED between the "SEC" pin and 5V it should start flash 1/s
return

RTC_Read:
I2C_Adr_B=0
I2CREAD SDA,SCL,RTC,I2C_Adr_B,[seconds,minutes, hours] ' in bcd code
return

call each part with a GOSUB

Good luck and enjoy

[Eng4444]

Hi,

If you dont use a backup battery for the 1307 make sure that the un-used leg for the backup function is tied to ground. You can find this in the datasheet but if this is not done the chip will not work properly (sometimes it doesn't, other times it does but never when you want it to).

We are using the 1307 and it is doing fine.


TRIS? = %00000000 ' all pins to output just replace ? with port name

SDA var Port?.? 'define port for I2C communication replace ?.? with pin
SCL var Port?.?

Hours var Byte
Minutes var Byte
Seconds var Byte
RTC var Byte
I2C_Adr_B var byte


RTC = % 11010000 ' Device adress on I2C bus
I2C_Adr_B=0

I2CWRITE SDA,SCL,RTC,I2C_Adr_B,[128,0,0,0,0,0,0,128] 'Reset time to 0 and stopped, 12 hour setting

Start_RTC:
I2C_Adr_B=0
I2CWRITE SDA,SCL,RTC,I2C_Adr_B,[0,0,0,0,0,0,0,16] 'Start RTC if you put a resistor and LED between the "SEC" pin and 5V it should start flash 1/s
return

RTC_Read:
I2C_Adr_B=0
I2CREAD SDA,SCL,RTC,I2C_Adr_B,[seconds,minutes, hours] ' in bcd code
return

call each part with a GOSUB

Good luck and enjoy

__________________________________________________ _____________

i wouldl ike to thank you so much! but now i returned home and far from my Lab. I will try it tomorrow. is it suitable for PIC16F876A? and by the way, how to set the date and time to: "10:15:30 01-06-2006 "? can you tell me how and in which part of your program?

thank you again....

[Eng4444]

call each part with a GOSUB

Good luck and enjoy

++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++

What do you mean by this?

could anyone explain to me?

of course i need it to show constantly the time and keep on incrementing seconds, minutes, hours, days...

so what is this GOSUB? and how to use it?
One more things, what to do if i want to set time and date as:
02:10:00 3-6-2006?

where to write them?in which sentence?

urgent help is needed because i am working right now on this...