Temperature Logging with Sync time & Date with GPS & Sending SMS!!

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Hello!! Everyone, I am sharing a Project on Data Logging to Memory Card using PIC18F8722 Micro-Controller, this project uses MDD Library of Microchip Application Framework and MPLAB C18 v3.40 Compiler with MPLAX 1.60.
The aim of this project is to create log of temperature, every one second along with time and date to be stored in Memory Card (I know creating log every second is not good), but one can change everything as per there requirement by changing the Source Code.
This Logging Project will average the temperature data from LM35 sensor 100 times and then store it in memory card, and it will also send this data to phone using SMS service. The SMS sending is done with the help of SIM300 Modem. Along with all this a GPS Module is also there, with the help of which UTC timing is updated with RTC DS1307 timing, date is also updated.
Data from GPS is not received continuously; it is received only when someone had pressed Key or when time reaches 59minutes.

GPS Packet
$GPRMC,114353.000,A,6016.3245,N,02458.3270,E,0.01,0.00,121009,,,A*69

SMS Format Received on Phone
10:59:01 09/01/13
TEMP= 020.9C
Lt = xx yy.ddddN/S
Lo= xxx yy.ddddW/E


This is the SMS Format one receive on its phone, SMS is received every hour and when someone press the button


Links are available to download

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The above project is having a small bug, i.e whenever the GPS is not sending correct date and time, then certain junk characters are displayed on lcd and stored in memory card.
This bug is removed in this code.
The links are added below, also have a description of the project with audio.
Note GPS is connected to receive pin of the UART1 while GSM Module is connected with the Transmitter pin of the UART1 of the micro-controller.
By this we are using 1 micro-controller UART to get and send data from two devices.

One more feature of this project, suppose satellite signals to the GPS module are not there, then time and date information are updated as per the old data without any disturbances they are sync only when valid data is coming from the gps module.
And if latitude and longitude are information is not valid then sms is sent without latitude and longitude.

Watch the video.

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Why not shadow a RTC (even if implemented in f/w) as backup to the GPS-derived clock?

I'd think you want to log as much info as is possible.

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i didnt get what you want to say

There is a function in mdd framework but i think it is used to provide time and date to file creation.

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You can have a clock routine in your code that syncs to the GPS clock periodically. That way when you lose the GPS, you still have legitimate timestamps.

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i think i am doig same
Whenever gps is giving time properly means it is a valid fix i update my rtc and time and date is syced, but if not , means gps time is not valid my rtc is having previous timme and it will keep running without any data loss.

i think this is what you are saying.

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yes