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[on:]

I am trying to make something using the Time library and the Ledcontroller library to turn a certain led on a certain given second.

I am not sure how variables and values work. And i worst don't know how to call one up.

The time library uses "second()" to determine current second.
For the ledcontroller i use the command "lc.setLed(0,2,6,true);" to turn on the led on the row 2, column 6

So i wanted to do something like

Code:

Librarys blah blah blah

int 01 = 2,6

void setup(){
blah blah
}

void loop(){
    lc.setLed(0,"second()",true);
}

I just don't understand C. Anyone can sheed some light on to my problem. I was at LadyAda/Adafruit website taking the tutorials.

[Reply #1 on:]

int 01 = 2,6

Well, variable names have to start with a letter or an underscore.

In C, a decimal point is a full-stop (period), not a European comma, and you can't asssign floating-point values to an "int" variable. (well, you can, but you'll only get the integer part).

You also need a semicolon to terminate every statement.

I'd start off simple, with some of the examples in the learning section, then pick them apart to see how C works.

[Reply #2 on:]

So now i get this "Illegal Const Char to Char conversion"

Code:

Librarys blah blah blah

// _## = seconds and "#,#" is the row and column value for the leds
const char _01 = "0,0";  //At second 01 the value will be 0,0
const char _02 = "0,1";  //At second 02 the value will be 0,1
const char _03 = "0,2";
.....
const char _58 = "7,3";
const char _59 = "7,4";  //At second 59 the value will be 7,1
const char _00 = "7,5";  //At second 00 the value will be 7,2


void setup(){
blah blah
}

void loop(){
    lc.setLed(0,"_second()",true);
}

also at the bottom where "lc.setLed(0,"_second()",true);" how can i make the second() to call up my variable and for the entire thing can work.

Sorry. i am a extreme n00b.

[Reply #3 on:]

A char can hold one character. A char array can hold more than one character.

A two dimensional array would solve your problem neatly. The first value would range from 0 to 59, and would be defined by the output from seconds. The second value would be a fixed size (4, in your case).

Code:

char stuff[60][4] = {"0,0", "0,1", "0,2", ... , "7,3", "7,4", "7,5"};

But, then:

Code:

char *ptr = stuff[second()];

would result in ptr = "7,3" when second() returned 57, which would need to be parsed (using strtok) and converted to integers (using atoi) to get the integer values that the LCD controller function is looking for.

You could use a 3 dimensional integer array.

[Reply #4 on:]

Well i am making some progress. Thank you

To work with this i try to debug it using the Serial Monitor.
My problem is that i get this Æ thingy appearing on my output for ptss and ptst. I bolded the main problem.

Code:

libarary BLAH BLAh

char sec2[60][1] = {
0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1,
2, 2, 2, 2, 2, 2, 2, 2,
3, 3, 3, 3, 3, 3, 3, 3,
4, 4, 4, 4, 4, 4, 4, 4,
5, 5, 5, 5, 5, 5, 5, 5,
6, 6, 6, 6, 6, 6, 6, 6,
7, 7}; //Tables

char sec1[60][1] = {
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1}; //Tables

void setup()  {
blah blah blah for serial output
}

void digitalClockDisplay(){
  Serial.print(second());  // digital clock display of the time
  Serial.print(" ");
  Serial.print(*ptss); //Displays one number of the first Array
  Serial.print(",");
  Serial.print(*ptst); //Displays one number of the second Array
  Serial.println();
}

void loop(){    
    digitalClockDisplay(); //Outputs the stuff in digitalClockDisplay on the serial monitor
    char *ptss = sec1[second()];
    char *ptst = sec2[second()];
   // lc.setLed(0,*ptss,true);
  }

  delay(1000);
}

I should be getting things like

01 00,01
02 00,02
..
59 07,00
00 07,01

but i get
01 Æ,Æ
02 Æ,Æ
...
59 Æ,Æ
00 Æ,Æ

[Reply #5 on:]

Serial.print(*ptss);

I don't see where or how you declared and initialised this pointer.

Could you post your real code (minus the "blah blah"s)?

(You may be missing a "DEC" or two)

[Reply #6 on:]

Code:

#include <LedControl.h>
#include <Time.h>  
#define TIME_MSG_LEN  11   // time sync to PC is HEADER followed by unix time_t as ten ascii digits
#define TIME_HEADER  'T'   // Header tag for serial time sync message
#define TIME_REQUEST  7    // ASCII bell character requests a time sync message

LedControl lc=LedControl(12,11,10,1);

char *ptss;
char *ptst;
char sec2[60][1] = {
0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1,
2, 2, 2, 2, 2, 2, 2, 2,
3, 3, 3, 3, 3, 3, 3, 3,
4, 4, 4, 4, 4, 4, 4, 4,
5, 5, 5, 5, 5, 5, 5, 5,
6, 6, 6, 6, 6, 6, 6, 6,
7, 7};
char sec1[60][1] = {
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1, 2, 3, 4, 5, 6, 7,
0, 1};

 void setup()  {
  Serial.begin(9600);
  setSyncProvider( requestSync);  //set function to call when sync required
  Serial.println("Waiting for sync message");
   /*
   The MAX72XX is in power-saving mode on startup,
   we have to do a wakeup call
   */
  lc.shutdown(0,false);
  /* Set the brightness to a medium values */
  lc.setIntensity(0,10);
  /* and clear the display */
}

void digitalClockDisplay(){
  // digital clock display of the time
  Serial.print(second());
  Serial.print(" ");
  Serial.print(*ptss);
  Serial.print(",");
  Serial.print(*ptst);
  Serial.println();
}

void printDigits(int digits){
  // utility function for digital clock display: prints preceding colon and leading 0
  Serial.print(":");
  if(digits < 10)
    Serial.print('0');
  Serial.print(digits);
}

void processSyncMessage() {
  // if time sync available from serial port, update time and return true
  while(Serial.available() >=  TIME_MSG_LEN ){  // time message consists of a header and ten ascii digits
    char c = Serial.read() ;
    Serial.print(c);  
    if( c == TIME_HEADER ) {      
      time_t pctime = 0;
      for(int i=0; i < TIME_MSG_LEN -1; i++){  
        c = Serial.read();          
        if( c >= '0' && c <= '9'){  
          pctime = (10 * pctime) + (c - '0') ; // convert digits to a number    
        }
      }  
      setTime(pctime);   // Sync Arduino clock to the time received on the serial port
    }  
  }
}

time_t requestSync()
{
  Serial.print(TIME_REQUEST,BYTE);  
  return 0; // the time will be sent later in response to serial mesg
}

void loop(){    
  if(Serial.available() )
  {
    processSyncMessage();
  }
  if(timeStatus()!= timeNotSet)  
  {
    digitalWrite(13,timeStatus() == timeSet); // on if synced, off if needs refresh  
    digitalClockDisplay();
    char *ptss = sec1[second()];
    char *ptst = sec2[second()];
   // lc.setLed(0,*ptss,true);
  }

  delay(1000);
  
}

I am sorry. I just didn't want to have like a very long annoying post

[Reply #7 on:]

So, you didn't initialise it.

Code:

char *ptss;

You need to remove the second declaration of the pointer for this construct to work.
You need to read about scope rules.

[Reply #8 on:]

I still don't get it

I read some scoping rules, but it got really advance. This is my first time doing C++

[Reply #9 on:]

You have a global variables named ptss and ptst.

In loop, you declare local variables with the same names, and initialize them. That has no effect on the global variables.

At the end of the if block in which the local variables ptss and ptst are declared, they go out of scope.

The function digitalClockDisplay references the global variables, which have never been initialized.

Even if you remove the declaration statements in the if block in loop, so that ptss and ptst refer to the global variables, the initialization does not take place until after the call to digitalClockDisplay.

Also, sec1[0][0] is set to 0, which is not the same as '0'.

Finally, since the stated goal was to use the values that ptss and ptst point to as arguments to the lc function, which requires integers, it seems to me that you should declare sec1 and sec2 to be integer arrays.

Last, but not least, there is a pattern to the values in sec1 and sec2 that means that you don't need to store them in an array.

sec1 = 60 % 8;
sec2 = 60 / 8;

[Reply #10 on:]

yeah... no idea...

could someone do some of the work for me. Except for the array. I would like to be able to change that if i need to.

[Reply #11 on:]

You're trying to run before you can walk.

Start looking at some of the tutorials, and work through them.
Try modifying them and expanding them.

[Reply #12 on:]

Thanks guys... you made me learn some stuff by myself.

You guys are my FRIENDS now...

i did manage to get it work. HORRAY!!!

[Reply #13 on:]

And you are our friend for sticking with it, and not giving up!

Congratulations!  8-)