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1. 

   tfcroft4
   Member

   Adafruit have 16x24 LED displays with Ht1632C chip, they supply an Arduino library.
   https://github.com/adafruit/HT1632

   The library has the following code to initialise the board - it is possible to cascade a number of boards with different select lines 'cs1' 'cs2' hence the different parameters.
   
HT1632LEDMatrix::HT1632LEDMatrix(uint8 data, uint8 wr, uint8 cs1) {
matrices = (HT1632 *)malloc(sizeof(HT1632));

   matrices[0] = HT1632(data, wr, cs1);
   matrixNum = 1;
   _width = 24 * matrixNum;
   _height = 16;
   }

   HT1632LEDMatrix::HT1632LEDMatrix(uint8 data, uint8 wr,
   uint8 cs1, uint8 cs2) {
   matrices = (HT1632 *)malloc(2 * sizeof(HT1632));

   matrices[0] = HT1632(data, wr, cs1);
matrices[1] = HT1632(data, wr, cs2);
matrixNum = 2;
_width = 24 * matrixNum;
_height = 16;
}


   In the Maple environment we don't have malloc. Could any one suggest a work around to initialise the array matrices[] with the HT1632 objects.

   Thanks
   Ted

   Posted 3 years ago #
2. 

   ventosus
   Member

   malloc is part of newlib (C library your code is linked to), so you should be able to use it.

   have you included stdlib.h?

   
#include <stdlib.h>


   if you don't want to use malloc (which is a good thing on microcontrollers IMHO), allocate the maximal space for 'matrices' statically in your class definition.

   I guess 'matrices' may be defined as a pointer right now:
   
class HT1632LEDMatirx {
...
HT1632 *matrices;
...
};


   If the maximal number of boards you cascade is 2, then simply change it to a static array:
   
...
HT1632 matrices[2];
...


   and get rid of the lines with malloc.

   Posted 3 years ago #
3. 

   tfcroft4
   Member

   V
   Thanks for that pointer.

   Allocating as a static array by changing

   class HT1632LEDMatrix : public Print {
   ...
   private:
   HT1632 *matrices ; to

   HT1632 matrices[NUM_OF_BOARDS];
   };
   makes some progress.

   However the constructor call (?)

   // use this line for single matrix
   HT1632LEDMatrix matrix = HT1632LEDMatrix(DATA, WR, CS1);

   to
   

   HT1632LEDMatrix::HT1632LEDMatrix(uint8  data, uint8  wr, uint8  cs1) {
     matrices[0] = HT1632(data, wr, cs1);
     matrixNum  = 1;
     _width = 24 * matrixNum;
     _height = 16;
   }

   gives this compiler error
   <BUILD>\HT1632.cpp: In constructor 'HT1632LEDMatrix::HT1632LEDMatrix(uint8, uint8, uint8)':
   <BUILD>\HT1632.cpp:7: error: no matching function for call to 'HT1632::HT1632()'
   <BUILD>\/HT1632.h:34: note: candidates are: HT1632::HT1632(int8, int8, int8, int8)
   <BUILD>\/HT1632.h:30: note: HT1632::HT1632(const HT1632&)

   HT1632.h line 34 has this definition:

   HT1632(int8 data, int8 wr, int8 cs, int8 rd = -1);

   I would welcome your thoughts.

   TF

   Posted 3 years ago #
4. 

   ventosus
   Member

   C++ wants to call a constructor of HT1632 without parameters upon array initialization, but none is defined. So you may just have to add a definition to the header:

   HT1632::HT1632() {...}

   Posted 3 years ago #
5. 

   tfcroft4
   Member

   V

   Thanks for the advice. It is taking my C++ knowledge forward.

   I added
   `HT1632::HT1632() {
   }'
   To the HT1632.h and HT1632.cpp files and the basicdemo.pde now compiles OK with the MAPLE IDE.

   Now to upload the file and test with the display to see if the magic works.
   Cheeers
   TF

   Posted 3 years ago #
6. 

   tfcroft4
   Member

   Here is an update.

   I now have a 3 unit display i.e. 16x72 running the example matrixshapes.pde on my Olimex OLIMEXINO-STM32 board the Olimex Maple Clone.

   The AdaFruit library above is driving 3 chained Holtek HT1632C display boards.

   I had to play around with the output pins but this works.

   
#define WR 9 // Olimex WR is CLOCK when writing YELLOW
#define DATA 10 // Olimex BLUE
#define CS1 11 // Olimex WHITE 1
#define CS2 12 // Olimex WHITE 2
#define CS3 14 // Olimex WHITE 3


   I added:
   
#include <stdlib.h>


   to HT1632.h as well to enable the call to malloc

   Posted 3 years ago #
7. 

   Molex1701
   Member

   Hello,
   Just had to create an account for this site so I could say thanks for this information. Had same trouble with this library as well an making a constructor with no arguments worked for it. Noticed some other libraries I use dont make a plane one like that either. Think I'll go add them to save trouble down the line.
   Good day.

   Posted 2 years ago #

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