B4R Tutorial RTC DS1302 Example

Hi,

this is an example of using the Real Time Clock DS1302 (from sunfounder).
There are two versions:
1. Manual: Set the time manual befor uploading. After uploading the time is logged every seconds by a timer.
2. Commands: Various commands are accepted via the serial line (using Asyncstream):

• set: Set the RTC time year, month , dayofmonth , hour , minute , second , dayofweek
• get: Get the RTC timeformat YYYY-mon-dayofweek hour:minute:second dayofweekname
  
• getbytes: Get the RTC time as an array of bytes with year, month , dayofmonth , hour , minute , second , dayofweek
• start / stop: Start & Stop Logging

Wiring

DS1302 ---- Arduino (Wirecolor)
SCL   ------- 7 yellow
SDA  ------- 6 brown
RST  ------- 5 white
VCC  ------- 3.3v red
GND ------- GND black

2016.06.2 First Version

• The DS1302 library is included. Copy to the Arduino IDE Libraries in folder ds1302.
• The code uses Inline C with ds1302.h included.
• Have not been successful with the attempt to wrap the library DS1302, therefor solved using Inline C.
• A type is used for the timestamp.
• Overall, must say, was not easy to get started - several wrapping attemps not successful, then finding best way to handle timestamp went back and forth ... but anyhow this is now working fine.
• Next: when the I2C LCD arrives will amend with a clock.
• Source code attached and documented.

2016.06.03 Update

• New library rDS1302 wrapping DS1302.
• Build two versions Manual and Commands using the rDS1302 Library.
• Attachment updated which contains:
• Example using Inline C with the DS1302 Library (rtcds1302-inlinec-command, rtcds1302-inlinec-manual).
• Example using the wrapped library rDS1302 (rtcds1302-lib-command, rtcds1302-lib-manual).
• Examples tested with an Arduino UNO and Sunfounder DS1302.
• The new rDS1302 is in the attachment folder Library rDS1302.

B4R Serial Connector example for setting the date & time. A must tool for testing.

 

[Erel]

This is how I would have wrapped this library.

I don't have this chip so I cannot fully test it.

 

[Toley]

The best way to test it is to use this kind of module available everywhere in different shape. (don't mind the link I've post it's random choice of a nice looking one).

 

[rwblinn]

This is how I would have wrapped this library.

I don't have this chip so I cannot fully test it.

First of all, thanks for taking the time and providing another great howto wrap a library example.
Have tested and received error:

In file included from sketch\B4RDefines.h:23:0,
                 from sketch\rDS1302.h:2,
                 from sketch\DS1302.cpp:6:
b4r_main.h:13: error: 'B4RDS1302' in namespace 'B4R' does not name a type
static B4R::B4RDS1302* _ds1302;
        ^
b4r_main.h:14: error: 'DSTime' in namespace 'B4R' does not name a type
static B4R::DSTime* _ds1302time;
        ^
exit status 1
'B4RDS1302' in namespace 'B4R' does not name a type

The B4R Code:

Sub Process_Globals
    Public Serial1 As Serial
    Public ds1302 As DS1302
    Public ds1302time As DSTime
    Public Timer1 As Timer
End Sub

Private Sub AppStart
    Serial1.Initialize(115200)
    SetRTCTime
    Timer1.Initialize("Timer1_Tick", 1000)
    Timer1.Enabled = True
End Sub

Sub SetRTCTime
    ds1302time.Initialize
    ds1302time.Years = 2016
    ds1302time.Months = 6
    ds1302time.DayOfMonth = 2
    ds1302time.Hours = 16
    ds1302time.Minutes = 53
    ds1302time.Seconds = 9
    ds1302time.DayOfWeek = 4
    ds1302.Initialize(5,6,7)
    ds1302.SetTime(ds1302time)
End Sub

Sub GetRTCTime
    Dim currenttime As DSTime = ds1302.CurrentTime
    Log("RTC Time ", _
        NumberFormat(currenttime.years,4,0), " ", NumberFormat(currenttime.months,2,0), "-", NumberFormat(currenttime.dayofmonth,2,0), _
        " ", _
        NumberFormat(currenttime.hours,2,0), ":", NumberFormat(currenttime.minutes,2,0), ":", NumberFormat(currenttime.seconds,2,0), _
        " ", _
        currenttime.dayofweek)
End Sub

Sub Timer1_Tick
    GetRTCTime
End Sub

 

[Erel]

It was a confusing mistake related to the #include order.
The attached library fixes this issue.

A single line was changed in DS1302.cpp:

#include "B4RDefines.h"

Instead of:

#include "rDS1302.cpp"

 

[rwblinn]

Thanks = tested and working. Build new examples and updated Post #1.

 

[Beja]

Hi rwblinn and thanks for the promising library..
Would you please redraw the circuit diagram with the module of the RTC instead of the chip?
The module has a lithium battery that will keep the TIME even if power is turned off. (for limited time though)

Thanks in advance.

 

[rwblinn]

Hi,

could not find a full DS1302 part in fritzing. Only the chip was listed - so took that one.
For the experiment, used a sunfounder RTC ds1302 with the pins marked:

 

[Mostez]

hello,
I followed your example and updated libraries as instructed, but i've got this strange results,

AppStart
RTC Time 2011 83-01 11:24:08 Tue
RTC Time 2016 06-03 16:48:11 Fri
RTC Time 2011 83-01 11:24:09 Tue
RTC Time 2016 06-03 16:48:13 Fri
RTC Time 2011 83-01 11:24:10 Tue
RTC Time 2016 06-03 16:48:15 Fri

i'm using Arduino Mega 2560 and I assembled the DS1302 board on test board, the very strange thing is, clock is running correctly but i don't know what is that 2011 line, I tested my DS1302 test board with this native arduino code and it worked OK


DS1302 Real Time Clock
Version 2, March 2013
Time = 10:08:00, Date(day of month) = 15, Month = 4, Day(day of week) = 2, Year = 2013
Time = 10:08:05, Date(day of month) = 15, Month = 4, Day(day of week) = 2, Year = 2013
Time = 10:08:10, Date(day of month) = 15, Month = 4, Day(day of week) = 2, Year = 2013
Time = 10:08:15, Date(day of month) = 15, Month = 4, Day(day of week) = 2, Year = 2013
Time = 10:08:20, Date(day of month) = 15, Month = 4, Day(day of week) = 2, Year = 2013
Time = 10:08:25, Date(day of month) = 15, Month = 4, Day(day of week) = 2, Year = 2013
Time = 10:08:30, Date(day of month) = 15, Month = 4, Day(day of week) = 2, Year = 2013

 

[rwblinn]

Hi,

thats strange. Just tested the DS1302 connected to an Arduino MEGA.
Versions used: Win 10, Arduino IDE 1.6.11, B4R 1.20, rDS1302 Lib 1.00.
Wiring

'DS1302 ---- Arduino MEGA =Wirecolor
'SCL ------- 8 =yellow
'SDA ------- 7 =brown
'RST ------- 6 =white
'VCC ------- 3.3v =red
'GND ------- GND =black

Init the DS1302

ds1302.Initialize(6,7,8)

Output

AppStart
RTC Time 2016 09-27 16:20:10 Tue
RTC Time 2016 09-27 16:20:11 Tue
RTC Time 2016 09-27 16:20:12 Tue
RTC Time 2016 09-27 16:20:13 Tue
RTC Time 2016 09-27 16:20:14 Tue
RTC Time 2016 09-27 16:20:15 Tue
RTC Time 2016 09-27 16:20:16 Tue

 

[Mostez]

I soldered 1uf decoupling capacitor close to ds1302 and replaced the 3V coin cell with fresh one, it works OK now. let me ask you one more question please, how can I change time format from 24H to 12H ?
Thanks

 

[Hans- Joachim Krahe]

my 1302 is to be set correctly, but does not count. Time keeps same. probably hardware bug?

 

[Mostez]

I faced same problem, the chip should be powered by 3.3V only, not 5V

 

[Mostez]

what module you're using? try to pull up RST, DAT and CLK pins with 10K resistors, did you connect the time keeping coin cell (CR1220 or CR2032)

 

[Hans- Joachim Krahe]

ok, works with inline now. Thanks)

 

[Hans- Joachim Krahe]

some of the clock modules seem to need short wires and some of them seem to be simply defect...

 

[Hans- Joachim Krahe]

what module you're using? try to pull up RST, DAT and CLK pins with 10K resistors, did you connect the time keeping coin cell (CR1220 or CR2032)

..you think, I need to pull em up? thought, they were defined as MODE_INPUT_PULLUP, but shurely, you can be right... thank you

time keeping cell is in, but makes no difference.

...no, pullup makes no changes!

 

[Hans- Joachim Krahe]

... there is an array problem with day of week on sunday too - the c#include adresses from 1 to 7, the b4a from 0 to 6

 

[Shay]

Hi
I also have this issue:
I can set the date and time, if I disconnect the usb from the nano, and connect back the time is ok (I assume battery is ok)
but time is not counting up (Same all the time)
how do I solve it? (I am using 3.3v)

 

[Shay]

seems to work ok if I use the rtcds1302-inlinec and not the rtcds1302-lib