/*
 * ----------------------------------------------------------------------------
 * "THE BEER-WARE LICENSE" (Revision 42):
 * <struppi@struppi.name> wrote this file. As long as you retain this notice you
 * can do whatever you want with this stuff. If we meet some day, and you think
 * this stuff is worth it, you can buy me a beer in return.
 * (c) 2014 Stefan Rupp
 * ----------------------------------------------------------------------------
 */


#include <string.h>
#include "led1642gw.h"
#include <util/delay.h>

#define NUM_LED1642GW_CHANNELS (16)
#define NUM_LED_CHANNELS (NUM_LED1642GW_CHANNELS*NUM_LED1642GW_ICs)
#define NUM_LED1642GW_ICs (3)

static uint16_t ledbuffer[NUM_LED_CHANNELS];


#define DDR_CLK (DDRC)
#define PORT_CLK (PORTC)
#define PIN_CLK (3)
#define SET_CLK_H() ((PORT_CLK) |=  (1<<(PIN_CLK)))
#define SET_CLK_L() ((PORT_CLK) &= ~(1<<(PIN_CLK)))

#define DDR_SDI (DDRC)
#define PORT_SDI (PORTC)
#define PIN_SDI (4)
#define SET_SDI_H() ((PORT_SDI) |=  (1<<(PIN_SDI)))
#define SET_SDI_L() ((PORT_SDI) &= ~(1<<(PIN_SDI)))

#define DDR_LE (DDRC)
#define PORT_LE (PORTC)
#define PIN_LE (2)
#define SET_LE_H() ((PORT_LE) |=  (1<<(PIN_LE)))
#define SET_LE_L() ((PORT_LE) &= ~(1<<(PIN_LE)))


static void write_data(uint16_t data, uint8_t le_clocks)
{
  uint16_t mask = 0x8000;
  int8_t bit;
  //PORTC &= ~(1<<PC2);
  SET_LE_L();
  for (bit=15; bit>=le_clocks; bit--) {
	//PORTC &= ~(1<<PC3);
	SET_CLK_L(); 
    if(data&mask) { SET_SDI_H(); }
    else { SET_SDI_L(); }
    //PORTC |= (1<<PC3);    
	SET_CLK_H();
    mask >>= 1;
  }
  
  //PORTC |= (1<<PC2);
  SET_LE_H();
  for (/*noting to initialize*/; bit>=0; bit--) {
	//PORTC &= ~(1<<PC3);
	SET_CLK_L();
    if(data&mask) { SET_SDI_H(); }
    else { SET_SDI_L(); }
    //PORTC |= (1<<PC3);    
	SET_CLK_H();
    mask >>= 1;
 }

  //PORTC &= ~(1<<PC3);
  SET_CLK_L();
  //PORTC &= ~(1<<PC2);
  SET_LE_L();
  //PORTC &= ~(1<<PC4);
  SET_SDI_L();
  
}


static void write_data_latch(uint16_t data)
{
  write_data(data, 4);
}

static void write_global_latch(uint16_t data)
{
  write_data(data, 6);
}

static void write_no_command(uint16_t data)
{
  write_data(data, 0);
}


void led1642gw_turn_all_on(void)
{
  
  write_data(0xffff, 2);
  _delay_us(10);
  write_data(0xffff, 2);
  _delay_us(10);
  write_data(0xffff, 2);
  _delay_us(10);
}


void led1642gw_turn_all_off(void)
{
  
  write_data(0x0000, 2);
  _delay_us(10);
  write_data(0x0000, 2);
  _delay_us(10);
  write_data(0x0000, 2);
  _delay_us(10);
}


void led1642gw_init(void)
{

  //PORTC &= ~(1<<PC3); // SCK
  SET_CLK_L();
  //PORTC &= ~(1<<PC4); // DATA
  SET_SDI_L();
  //PORTC &= ~(1<<PC2); // LE
  SET_LE_L();
  //DDRC |= (1<<PC3); // SCK
  DDR_CLK |= (1<<PIN_CLK);
  //DDRC |= (1<<PC4); // DATA
  DDR_SDI |= (1<<PIN_SDI);
  //DDRC |= (1<<PC2); // LE
  DDR_LE |= (1<<PIN_LE);
  memset(ledbuffer, 0x00, sizeof(ledbuffer));
  led1642gw_flush();
}


void led1642gw_flush(void)
{
  uint8_t channel;
  uint8_t ic;
  for (channel=0; channel<NUM_LED1642GW_CHANNELS-1; channel++) {
	  for (ic=0; ic<(NUM_LED1642GW_ICs-1); ic++) {
		  write_no_command(ledbuffer[channel+(NUM_LED1642GW_CHANNELS*ic)]);
	  }
	  write_data_latch(ledbuffer[channel+(ic*NUM_LED1642GW_CHANNELS)]);
  }
  for (ic=1; ic<NUM_LED1642GW_ICs; ic++) {
	  write_no_command(ledbuffer[(ic*NUM_LED1642GW_CHANNELS)-1]);
  }
  write_global_latch(ledbuffer[(ic*NUM_LED1642GW_CHANNELS)-1]);

}


void led1642gw_set_channel(uint8_t channel, uint16_t value)
{
  if (channel < NUM_LED_CHANNELS) {
    ledbuffer[channel] = value;
  }

}


void led1642gw_clear(void)
{
  memset(ledbuffer, 0x00, sizeof(ledbuffer));
}