/* This program was used to find a fault in the software. Note that the in the function 
write_byte the clk wa not pulled low after send 1 bit hence the next bit was not sent.
Adiitionally note that before initialization the clk was again pulled low for 
extra precaution*/



#include "hal.h"
#include "bitmap.h"

// define pins
#define CLK A_1
#define CS A_3
#define DIN A_5

//define here number of matrix modules used
#define number_of_modules 2

void setup(){
  matrix_init();
  write_same_display(fill_all);//fill_all is array in bitmap.h that fills all rows
}

void loop(){

}

//active low cs
void cs_active()
{
  pin_write(CS,0);
}
void cs_idle()
{
  pin_write(CS,1);
}

void clk_high(){
  pin_write(CLK,1);
}

void clk_low(){
  pin_write(CLK,0);
}
void write_byte(volatile uint8_t user_byte)
{
  //Send 8 bits starting from MSB
  for(volatile uint8_t bits=0;bits<8;bits++) 
  {
    user_byte&0x80?pin_write(DIN,1):pin_write(DIN,0);
    user_byte=user_byte<<1;
    clk_high();
    for(volatile uint8_t i=0;i<2;i++);//keep signal stable for some time
    clk_low();//Deliberatily pull it low for next bit
  }
}

void send(volatile uint8_t addr,volatile uint8_t data)
{
  cs_active();
  for(volatile uint8_t i=0;i<number_of_modules;i++)
  {
    write_byte(addr);
    write_byte(data);
  }
  cs_idle();
}

void matrix_init(){
  init_pin(CLK,output);
  init_pin(CS,output);
  init_pin(DIN,output);
  clk_low();//make clk low while initialization
  cs_idle();//make CS idle while initialization
  send(0x0C,0x01);//Normal mode
  send(0x09,0x00);//No decoding
  send(0x0A,0x08);//Intensity 17/32
  send(0x0B,0x07);
}

//A testing function to check if all modules are working properly
//This will display same output through all modules
void write_same_display(volatile uint8_t *data_Arr)
{
  for(volatile uint8_t row=1;row<9;row++)
  {
    cs_active();
    for(volatile uint8_t modules=0;modules<number_of_modules;modules++)
    {
      write_byte(row);
      write_byte(data_Arr[row-1]);
    }
    cs_idle();
  }
}