#include "fpga_control.h"

void fpga_init(void)
{
  //First set pin high in data register to avoid spikes when changing from input to output
  FPGA_CLK_INIT();
  
  //Initialize the three control lines for output
  FPGA_CTRL_INIT();
}


void fpga_write_cmd(unsigned char command)
{
  //Set the control lines for writing a command
  FPGA_CMD_WRITE();

  //Set the bus for writing
  FPGA_BUS_DIR_OUT();

  //Write the data to the bus  
  FPGA_SET_DATA(command);
  
  //Clock the data into the FPGA
  FPGA_PULSE_CLK();
}

unsigned char fpga_read_cmd(void)
{
  //Set the bus for reading
  FPGA_BUS_DIR_IN();
  
  //Set the control lines for reading a command
  FPGA_CMD_READ();

  //Clock the data to the output of the FPGA
  FPGA_PULSE_CLK();
 
  //Read the data
  return(FPGA_GET_DATA());
}

void fpga_write_byte(unsigned char data)
{
  //Set the control lines for writing a command
  FPGA_DATA_WRITE();

  //Set the bus for writing
  FPGA_BUS_DIR_OUT();
  
  //Write the data to the bus  
  FPGA_SET_DATA(data);
  
  //Clock the data into the FPGA
  FPGA_PULSE_CLK();
}

unsigned char fpga_read_byte(void)
{
  //Set the bus for reading
  FPGA_BUS_DIR_IN();
  
  //Set the control lines for reading a command
  FPGA_DATA_READ();

  //Clock the data to the output of the FPGA
  FPGA_PULSE_CLK();
 
  //Read the data
  return(FPGA_GET_DATA());
}

void fpga_write_short(unsigned short data)
{
  //Set the control lines for writing a command
  FPGA_DATA_WRITE();

  //Set the bus for writing
  FPGA_BUS_DIR_OUT();
  
  //Write the msb to the bus  
  FPGA_SET_DATA(data >> 8);
  
  //Clock the data into the FPGA
  FPGA_PULSE_CLK();
  
  //Write the lsb to the bus  
  FPGA_SET_DATA(data);
  
  //Clock the data into the FPGA
  FPGA_PULSE_CLK();
}

unsigned short fpga_read_short(void)
{
  unsigned short data;
  
  //Set the bus for reading
  FPGA_BUS_DIR_IN();
  
  //Set the control lines for reading a command
  FPGA_DATA_READ();

  //Clock the data to the output of the FPGA
  FPGA_PULSE_CLK();

  //Get the msb
  data = FPGA_GET_DATA() << 8;

  //Clock the data to the output of the FPGA
  FPGA_PULSE_CLK();

  //Get the lsb
  data |= FPGA_GET_DATA();
  
  //Read the data
  return(data);
}