RTC example for XC167

The following code is what I am trying to get to run. The interrupt is only there for testing, in the production code I do not really need it (so RTC_IC_IE = 1; is only there to do some testing now).

The interrupt, however, never occurs. And when calling RtcGetTime, it always returns 0. In the debugger T14 is always 0 and is never incremented.

During startup, the syscon register is set so the RTC runs synchronously to enable me to read/write the RTC registers.

Since I do not have an auxillary oscillator, I cannot try to run with RTC_CON = 0x8003.

interrupt (0x5D) void RTC(void)
{
    if (T14IR == 1)
    {
        T14IR = 0;
        if (P3_7 == 1)
        {
            P3_7 = 0;
        }
        else
        {
            P3_7 = 1;
        }
    }
}

int RtcInit(void)
{
    int nResult = 0;

    if ((ACCPOS == 0) || (_getbit(SYSCON3, 14) == 1))
    {
        /* No write access possible or RTC HW disabled */
        nResult = -1;
    }
    else
    {
        RTC_CON = 0x8013;
        RTC_T14REL = 0x0010;
        RTC_RELL = 0x0020;
        RTC_RELH = 0x0030;
        RTC_IC = 0x7F;
        T14IE = 1;
        RTC_IC_IE = 1;
    }
    return nResult;
}

void RtcSetTime(tTimeOfDay time)
{
    RTC_T14  = time.msecOfDay & 0x0FFFFFFFL;
    RTC_RELL = 0;
    RTC_RELH = time.days << 6;
}

void RtcGetTime(tTimeOfDay *pTime)
{
    pTime->msecOfDay = RTC_T14 & 0x0FFFFFFFL;
    pTime->days      = RTC_RTCH >> 6;
}

The following code is what I am trying to get to run. The interrupt is only there for testing, in the production code I do not really need it (so RTC_IC_IE = 1; is only there to do some testing now).

The interrupt, however, never occurs. And when calling RtcGetTime, it always returns 0. In the debugger T14 is always 0 and is never incremented.

During startup, the syscon register is set so the RTC runs synchronously to enable me to read/write the RTC registers.

Since I do not have an auxillary oscillator, I cannot try to run with RTC_CON = 0x8003.

interrupt (0x5D) void RTC(void)
{
    if (T14IR == 1)
    {
        T14IR = 0;
        if (P3_7 == 1)
        {
            P3_7 = 0;
        }
        else
        {
            P3_7 = 1;
        }
    }
}

int RtcInit(void)
{
    int nResult = 0;

    if ((ACCPOS == 0) || (_getbit(SYSCON3, 14) == 1))
    {
        /* No write access possible or RTC HW disabled */
        nResult = -1;
    }
    else
    {
        RTC_CON = 0x8013;
        RTC_T14REL = 0x0010;
        RTC_RELL = 0x0020;
        RTC_RELH = 0x0030;
        RTC_IC = 0x7F;
        T14IE = 1;
        RTC_IC_IE = 1;
    }
    return nResult;
}

void RtcSetTime(tTimeOfDay time)
{
    RTC_T14  = time.msecOfDay & 0x0FFFFFFFL;
    RTC_RELL = 0;
    RTC_RELH = time.days << 6;
}

void RtcGetTime(tTimeOfDay *pTime)
{
    pTime->msecOfDay = RTC_T14 & 0x0FFFFFFFL;
    pTime->days      = RTC_RTCH >> 6;
}

Oops,

In the previous example, RtcSetTime is incorrect as it needs to write to RTC_RTCH and RTC_RTCL instead of writing to RTC_RELL and RTC_RELH;

But even with this improvement it does not work :-(

void RtcSetTime(tTimeOfDay time)
{
    RTC_T14  = time.msecOfDay & 0x0FFFFFFFL;
    RTC_RTCL = 0;
    RTC_RTCH = time.days << 6;
}

Now I understand better. Unfortunately I use the C167CS which is different than the XC167. As we are using different processors, I don't think I can help you.

Are you sure that you are writing to the RTC_CON register?

Try writing to the RTC_CON register last, after the write to RTC_IC_IE.

In your init routine, call the RtcSetTime routine to set a time. Set a non-zero time. When you call RtcGetTime you should at the very least see the non-zero time.

Sorry that I couldn't help. If you figure it out, perhaps you could post the solution here.