CCS/MSP430FR6989: RTC for Timestamp

Hello Vijay,

We will look into this and get back to you.

Thanks,

Yiding

I like to use NTP or SNTP to update the RTC clock. Please point me to any example with does this

I want to pull time from my server in int (dd, yy, mm, dow, h, m, s) and I want to update the RTC Calendar with integer values. When I try to update the clock i am not getting the right values into it. It tried both BCD mode and Hex mode.

Below is the extract of my code.

#include <msp430fr6989.h>
#include "myprintf.h"

#define changeHexToInt(hex)     ( ( ((hex)>>4) *10 ) + ((hex)%16) )

int mm = 10;
int dd = 18;
int yy = 2019;
int h = 13;
int m = 17;
int s = 44;

int main (void)
{
    WDTCTL = WDTPW | WDTHOLD;

    // Init UART_A1 Pins
    P3SEL0 |= BIT4 | BIT5;                  // Pins P3.4(TX) P3.5(RX)
    P3SEL1 &= ~(BIT4 | BIT5);               // USCI_A1 UART operation using Backchannel

    // Init LFXT Pins
    PJSEL0 = BIT4 | BIT5;                   // PJ.4(LFXIN), PJ.5(LFXOUT)

    PM5CTL0 &= ~LOCKLPM5;

    // Configure LFXT 32kHz crystal
    CSCTL0_H = CSKEY >> 8;                  // Unlock CS registers
    CSCTL4 &= ~LFXTOFF;                     // Enable LFXT
    do
    {
      CSCTL5 &= ~LFXTOFFG;                  // Clear LFXT fault flag
      SFRIFG1 &= ~OFIFG;
    } while (SFRIFG1 & OFIFG);              // Test oscillator fault flag
    CSCTL0_H = 0;                           // Lock CS registers

    Sync_Time();

    RTCCTL0_H = RTCKEY_H;                   // Unlock RTC
//    RTCCTL0_L = RTCTEVIE | RTCRDYIE;        // enable RTC read ready interrupt
                                            // enable RTC time event interrupt

    RTCCTL1 = RTCHOLD | RTCMODE | RTCBCD;   // RTC enable, BCD mode, RTC hold

    RTCYEAR = yy;                       // Year = 0x2010
    RTCMON = mm;                           // Month = 0x04 = April
    RTCDAY = dd;                          // Day = 0x06 = 6th
    RTCDOW = dow;                          // Day of week = 0x04 = Thursday
    RTCHOUR = h;                         // Hour = 0x15
    RTCMIN = m;                          // Minute = 0x47
    RTCSEC = s;                          // Seconds = 0x50

    RTCCTL1 &= ~(RTCHOLD);

    while(1)
    {
        myprintf("RTC: %02d%02d-%02d-%02d %02d:%02d:%02d\r\n",
                 (long int)changeHexToInt(RTCYEAR >> 8),
                 (long int)changeHexToInt(RTCYEAR & 0x00FF),
                 (long int)changeHexToInt(RTCMON),
                 (long int)changeHexToInt(RTCDAY),
                 (long int)changeHexToInt(RTCHOUR),
                 (long int)changeHexToInt(RTCMIN),
                 (long int)changeHexToInt(RTCSEC)
                 );
        __delay_cycles(5000000);
    }
}

In the terminal it prints

0843-10-12 13:11:32

Where as it should print

2019-10-18 13:17:44

Please help.

Regards

Vijay

> int m = 17;

>0843-10-12 13:11:32

(int)17 is 0x11 which is "11" in BCD, so it's doing what you told it to do. You need to change your "int"-s to BCD before storing them.

If it helps, I think you can store the "int" in HEX mode, then change the RTC to BCD mode, and it will read out in BCD.

There are also the BIN2BCD and BCD2BIN registers to do this for you.

I have tried changeIntoToHex from one of the examples and used it in BCD mode. It is working for all except for the year 2019.

#define changeIntToHex(dec)     ( ( ((dec)/10) <<4 ) + ((dec)%10) )

Please help me with the year

It would probably look something like [untested]:

> highBCD=changeIntToHex(year_in_BIN/100);

> lowBCD=changeIntToHex(year_in_BIN%100);

>year_in_BCD = (highBCD << 8) | (lowBCD << 0);

though I would be tempted to say instead:

> BIN2BCD = year_in_BIN;  // uint12 goes in,

> year_in_BCD = BIN2BCD; // BCD comes out

Dear Yiding

The changeIntToHex is working fine. I only have issue with the year. I am receiving the year 2019 in Int using time.h. The following is not working.

RTCYEAR = changeIntToHex(2019);

I also tried

RTCYEAR_H = changeIntToHex(20);

RTCYEAR_L = changeIntToHex(19);

Both are not working either in BCDMODE or HEXMODE. However, others like mins, hours etc are working as below

RTCSEC = changeIntToHex(newtime->tm_sec);
RTCMIN = changeIntToHex(newtime->tm_min); 
RTCHOUR = changeIntToHex(newtime->tm_hour); 
RTCDAY = changeIntToHex(newtime->tm_mday); 
RTCDOW = changeIntToHex(newtime->tm_wday);
RTCMON = changeIntToHex(newtime->tm_mon+1);

I need to do the same with year it fails

RTCYEAR = changeIntToHex(newtime->tm_year);

> RTCYEAR = changeIntToHex(2019);

This doesn't work since changeIntToHex is only designed to work on bytes (<100).

----------

> RTCYEAR_H = changeIntToHex(20);

> RTCYEAR_L = changeIntToHex(19);

This doesn't work since you can't write RTCYEAR by bytes [Ref UG (SLAU367O) Table 29-2, footnote p. 732]. (I actually tried it; I couldn't figure out what it does, but it clearly isn't what you want.)

---------

Each of my suggested sequences above does what you want (when I do it). Did you try either of them?

---------

[Edit: Did you remember to unlock the RTC registers with "RTCCTL0_H = 0xA5;"?]

I tried your suggestion like below

RTCYEAR = (changeIntToHex(newtime->tm_year/100)<<8) | (changeHexToInt(newtime->tm_year%100)<<0);

I got below

Clock: 025-11-03 18:22:22

When you mentioned year_in_BIN should I convert the int to binary?

1) (int)25 is 0x19, which suggests you're not using changeHexToInt to change it back to integer ("binary") before printing it.

2) What value is actually in tm_year? If it's a time_t, I would expect it to contain 119 (2019-1900), but it appears to contain 19 (2019-2000). What is the origin of this structure?

----------

In my example, year_in_BIN is expected to be =(int)2019, e.g.

> int year_in_BIN = yy;  // yy = 2019 from the original example

----------

Unsolicited: Do you really need to use BCD at all? Your time_t values are binary ("int"), you want to print them in binary ("%d"), and the RTC registers can be set/read in binary ("HEX"). Dealing with BCD seems like a lot of trouble for no benefit. (I suspect the only reason that BCD mode exists in the RTC_C is that historically many RTCs ran only in BCD mode. BCD was actually easier to print in the days before printf.)

IT WORKED! THANK YOU SO MUCH!

i am using time_t values. There was a typo in the line. The code had changeHexToInt instead of changeIntToHex. I have used the following and now I am getting the year right.

RTCSEC = changeIntToHex(newtime->tm_sec); // Seconds = 0x50
RTCMIN = changeIntToHex(newtime->tm_min); // Minute = 0x47
RTCHOUR = changeIntToHex(newtime->tm_hour); // Hour = 0x15
RTCDAY = changeIntToHex(newtime->tm_mday); // Day = 0x06 = 6th
RTCDOW = changeIntToHex(newtime->tm_wday); // Day of week = 0x04 = Thursday
RTCMON = changeIntToHex(newtime->tm_mon+1); // Month = 0x04 = April
RTCYEAR = (changeIntToHex(newtime->tm_year-99)<<8) | (changeIntToHex(newtime->tm_year-100)<<0);

RTCYEAR = (changeIntToHex(newtime->tm_year-99)<<8) | (changeIntToHex(newtime->tm_year-100)<<0);

Clock: 2019-11-04 10:30:41 IST

Like you suggested I tried using the HEXMODE with the same code returns

Clock: 019-01-04 10:17:18 IST

It should be

Clock: 2019-10-04 10:57:18

What I did not understand is that even though RTC is in BCD MODE, I am still sending it in hex and it is working fine. If I change to HEX mode and send the same it does not work. Please enlighten me on this. Thank you for your time and support. I really appreciate it.

changeIntToHex() returns a BCD representation of the given int ("binary") value. The name seemed a bit odd to me, but I'm not the judge.