GPS Clock Time Adjusted to Timezone and Daylight Saving Time

In this instructable I share with you my gathering of useful components in Arduino code.

If you have a GPS receiver, why not use the time of the GPS satellites displayed in the time of your timezone.

Inspired by https://www.instructables.com/id/Adjusting-GPS-Dat...

Step 1: Components and Assemblation

Components

I used the following components, readily available from Aliexpress, eBay or Amazon

Arduino nano 5v, 168P

GPS receiver: GY-NEO6MV2

LCD screen with I2C connection

Breadboard

Jumper cables

Connections

Arduino:

GND to GND of LCD and GPS

5V to VCC of LCD and GPS

A4 to SDA of LCD (I2C bus)

A5 to SCL of LCD (I2C bus)

8 to TX of GPS (8 is RX as AltSoftwareSerial defined)

9 to RX of GPS (9 = TX as AltSoftwareSerial defined)

(in the photo a used other software serial pins in the standard library)

Step 2: Coding

I used the following libraries:

Timezone.h to adjust the time to daylight savings time

TinyGPS++ to decode the GPS data

AltSoftSerial.h for the software serial connection with the GPS module (works better than SoftwareSerial, as seen in the unwanted 'blinks' of the LCD screen, while using that standard).

EDIT: NewLiquidCrystal (NOT: LiquidCrystal_I2C.h) for the LCD screen I used.

These libraries can be downloaded from Github.

My code is published on my Github.

Comments

[Samarei]

Does it require a fix to get the time or is one satellite enough? Because TinyGPS++ doesn't seem to support $GPZDA which "is sent as soon as time is received from a satellite" (without needing a fix).

[Wim3d]

I have not tried that. I think it does not only depend on the TinyGPS++ library, but also on the GPS module. The module I used seems to start to send data when there is a fix. Maybe you can find a module which sends the time when receiving data from 1 satellite only, but then you need to interpret the data.

[Samarei]

Thanks for the reply!
On this video, at 2:50, the data seems to be sent before the GPS fix at 3:30:


Does yours work indoors even when a phone in GPS only mode with wifi disabled can't get a fix?

[Wim3d]

I checked it. The module indeed communicates the time before there is a GPS-fix. Instead of waiting for the satellite-value to be > 0, for a clock it is better to wait for 'gps.time.isValid()'. I changed the code in my Github.

[Samarei]

Wow, great! Thanks, that was fast!
Did you check if you're able to get a signal further away form the window?
PS: you missed the comment "wait for a GPS fix to know the UTC time"

[Wim3d]

Thanks for reviewing the code.
Yes the device is much more sensitive and gets a time faster and futher away from windows. I did not examine my entire house.

[Samarei]

You're welcome. ;)
Nice!
I was checking the code of TinyGPS++ and noticed that the date isn't always set when the time is set. The date is set with $GPRMC but not with $GPGGA.
So you may want to double check you can still get the date with one satellite (by just using gps.date.isValid() instead of gps.time.isValid()), otherwise $GPZDA will have to be used.

[Wim3d]

In my code, the arduino waits when the number of satellites is equal to zero. The number of satellites is > 0 when there is a fix and the number of satellites then is 4 or 5. I have not tried to get the time without a fix.
If I look at the video, apparently it is possible. If it is helpful for you I can try for my GPS module.
When using the uBlox sofware you can see that the GPS module sends data, even when there is no fix.
I live in a concrete house. My GPS module only works close to a large window or on the top floor, since the roof is not made of concrete.

[Samarei]

Indeed, it would be interesting to try. You'll probably be able to get the time away from the window since only one satellite signal is needed.
The code from the video is the DeviceExample example file.
You can just replace gps.satellites.value() != 0 by gps.time.isValid()

[Wim3d]

Indeed, this is the way I found out simultaneously and changed the code.

[RudyardB]

HELLO TAKES ME OUT OF THIS ERROR LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); // Set the LCD I2C address

[RudyardB]

ALREADY WORKED THIS WAS THE ERROR, WHAT I MISS IS FINDING TIMEZONE FOR CENTRAL MEXICO CONGRATULATIONS YOU ARE A TITAN

[Wim3d]

Thanks.
Suggestion: you can easily find I2C devices and their address by using a I2C scanner program on your Arduino.
For the timezone: please try this part of the code.
//CDT – Central Daylight Time / Central Daylight Saving Time (Daylight Saving Time) -300 = -5 hours from UTC in daylight saving time (summer).
TimeChangeRule CDT = {"CDT", Last, Sun, Mar, 2, -300};
//CST – Central Standard Time / Central Time (Standard Time) -360 = -6 hours from UTC in normal time (winter).
TimeChangeRule CST = {"CST ", Last, Sun, Oct, 3, -360};
Timezone CE(CDT, CST);

[Wim3d]

Hello. Can you give me more Information concerning your error or problems?

[RudyardB]

Hola al momento de compilar me muestra este error:
LiquidCrystal_I2C lcd (0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVO); // Establecer la dirección LCD I2C
y no lo puedo subir a la placa arduino

[RudyardB]

ESTE ES PA PANTALLA DE EROR

[Wim3d]

It seems that 'POSITIVE' is not defined (see the information in the red bar on your screen). I'm not sure where that's done, I guess in the Arduino board definitions.
I see that you use Arduin IDE 1.6.11. I suggest you updrade the Arduino IDE to the latest version (I use 1.8.9). If that does not work, try to update the libraries used. Good luck, let me know if you succeed or need any further help.

[RudyardB]

HELLO AND UPDATE TO THE LATEST VERSION AND LIBRARIES AND I HAVE THE SAME ERROR I WILL SEND YOU WHAT COMES IN THE RED LETTERS
Arduino:1.8.12 (Windows 8.1), Tarjeta:"Arduino Nano, ATmega328P"
GPS-clock-daylight-LCD:11:53: error: 'POSITIVE' was not declared in this scope
LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); // Set the LCD I2C address
^~~~~~~~
C:\Users\RUDYARD\Desktop\GPS-clock-daylight-LCD\GPS-clock-daylight-LCD.ino: In function 'void setup()':
GPS-clock-daylight-LCD:31:18: error: no matching function for call to 'LiquidCrystal_I2C::begin(int, int)'
lcd.begin(16, 2); // initialize the lcd for 16 chars 2 lines, turn on backlight
^
In file included from C:\Users\RUDYARD\Desktop\GPS-clock-daylight-LCD\GPS-clock-daylight-LCD.ino:9:0:
C:\Users\RUDYARD\Documents\Arduino\libraries\Arduino-LiquidCrystal-I2C-library-master/LiquidCrystal_I2C.h:76:7: note: candidate: void LiquidCrystal_I2C::begin()
void begin();
^~~~~
C:\Users\RUDYARD\Documents\Arduino\libraries\Arduino-LiquidCrystal-I2C-library-master/LiquidCrystal_I2C.h:76:7: note: candidate expects 0 arguments, 2 provided
Se encontraron varias bibliotecas para "Wire.h"
Usado: C:\Program Files (x86)\Arduino\hardware\arduino\avr\libraries\Wire
No usado: C:\Users\RUDYARD\Documents\Arduino\libraries\Wire
Se encontraron varias bibliotecas para "TinyGPS++.h"
Usado: C:\Users\RUDYARD\Documents\Arduino\libraries\TinyGPSPlus-0.95
No usado: C:\Users\RUDYARD\Documents\Arduino\libraries\TinyGPSPlus-1.0.2b
exit status 1
'POSITIVE' was not declared in this scope
Este informe podría contener más información con
"Mostrar salida detallada durante la compilación"
opción habilitada en Archivo -> Preferencias.

[Wim3d]

I found out the problem. I was my error, I am sorry. Since I have many libraries installed, I pointed you to the wrong library. This is the right library to install: https://github.com/fmalpartida/New-LiquidCrystal. I just changed it in my Instructable.
Please remove the LiquidCrystal_I2C.h library

[RudyardB]

HELLO FRIEND I DID EVERYTHING AND THE ERROR CONTINUES