BCD Conversion

[Ian Rogers]

sprint() calls itoa anyway!! So you are kinda using it!!

 

[TucsonDon]

I found this code online and it works perfect for reading from the RTC in BCD and converting to binary to display on the LCD

void TransformTime(void)
{
    hours    =  (((hours & 0xF0)  >> 4)*10  + (hours & 0x0F)) & 0x3F;   // Transform hours
    year     =   (year & 0xC0) >> 6;                                     // Transform year
    day      =  (((day & 0x30) >> 4)*10    + (day & 0x0F)) & 0x3F;      // Transform day
    month    =  (((month & 0x10)  >> 4)*10 + (month & 0x0F)) & 0x3F;    // Transform month
}

now I need to go the other way to send BCD to the RTC when set the time

 

[Pommie]

Ian Rogers with this format I no longer need itoa is that correct?

Correct.

Edit, when I posted this the two replies above weren't showing.

Mike.

 

[Pommie]

As I said in post 7 to go from binary to bcd add (bin/10)*6.
I.E
bcd=bin+((bin/10)*6);
OR
num+=(num/10)*6;

Mike.

 

[Ian Rogers]

As I said in post 7 to go from binary to bcd add (bin/10)*6.
I.E
bcd=bin+((bin/10)*6);
OR
num+=(num/10)*6;

Mike.

You're as bad as me..... 16 not 6

 

[Pommie]

You're as bad as me..... 16 not 6

Let's see,

47 decimal in BCD is 0x47 = 73 binary.

47+((47/10)*6 is 47+4*6 = 73 = correct

Your adding the difference between 10 and 16.

Mike.

 

[Ian Rogers]

Sorry! I bow to your algorithm... Not usually the way I do it.. I'm too used to shifting!!

 

[TucsonDon]

Gentlemen, thank you for your input. Pommie I had looked at Ian's algorithm in post #8 but had read right over yours, thanks for pointing it out.

 

[TucsonDon]

typedef unsigned char bool;
union
{
    struct
    {
        bool pumptimer1:1;      /*using the bits to flag if */
        bool pumptimer2:1;      /*a run timer is in use*/
        bool pumptimer3:1;
        bool pumptimer4:1;
        bool pumptimer5:1;
        bool pumptimer6:1;
        bool pumptimer7:1;
        bool pumptimer8:1;
    };
}pmptmr;        //pump timer status

  ++bb;
    timer 0x01 <<bb;            //bit shift to the left "bb" times
    if (pmptmr && timer &= On)
    {
        I2C1_MasterRead(*pdata,3,RTCC,*pflag);
    }

I am setting up a timer to start and stop a pump. The RTC has 240x8 bytes that I am using in five byte blocks. I am using the above struct to flag which timers are in use. I am tring to mask pmptmr with timer (and bit shifting) to pick out which are active but I need help to get it to work