#include <xs1.h>
#include <platform.h>
#include <print.h>

#include "xperipherals_uart.h"

#ifdef XPERIPHERALS_UART_1

#if XPERIPHERALS_UART_1__SUPPORT_TX
	//on tile[XPERIPHERALS_UART_1__TILE_NUMBER] :
    out port _xperipherals_uart_1__port_txd = XPERIPHERALS_UART_1__TXD_PORT;
	//#if $setting.handshake-mode == 1 // CTS/RTS
	//	on tile[$resource.tile-number] : out port _xperipherals_uart_1__port_rts = $resource.rts-port;
	//#endif
#endif

#if XPERIPHERALS_UART_1__SUPPORT_RX
	//on tile[XPERIPHERALS_UART_1__TILE_NUMBER] :
    in port _xperipherals_uart_1__port_rxd = XPERIPHERALS_UART_1__RXD_PORT;
	//#if $setting.handshake-mode == 1 // CTS/RTS
	//	on tile[$resource.tile-number] : out port _xperipherals_uart_1__port_cts = $resource.cts-port;
	//#endif
#endif

int   _xperipherals_uart_1__period = 0;
int   _xperipherals_uart_1__wbusy;
int   _xperipherals_uart_1__rbusy;
xbyte _xperipherals_uart_1__wdata;
xbyte _xperipherals_uart_1__rdata;
timer _xperipherals_uart_1__timer;
xuint _xperipherals_uart_1__time;
xuint _xperipherals_uart_1__count;

#define REFERENCE_CLOCK_FREQUENCY 100000000

// Initialize internal data and state information, configure clocks and ports

void xperipherals_uart_1__initialize( void )
{
    timer _xperipherals_uart_1__timer;
	#if XPERIPHERALS_UART_1__SUPPORT_TX
    int time;
    _xperipherals_uart_1__port_txd <: 1;
	//#if $setting.handshake-mode == 1
	//_xperipherals_uart_1__port_rts <: 1;
	//#endif
    _xperipherals_uart_1__timer :> time;
    time += 10 * _xperipherals_uart_1__period;
    _xperipherals_uart_1__timer when timerafter(time) :> void;
	#endif

	#if XPERIPHERALS_UART_1__SUPPORT_RX
	//#if $setting.handshake-mode == 1
	//_xperipherals_uart_1__port_cts <: 1;
	//#endif
	#endif

	_xperipherals_uart_1__wbusy = _xperipherals_uart_1__rbusy = FALSE;
}

// Configure clocks for a new MCLK frequency or sample rate

void xperipherals_uart_1__configure( xuint baud_rate, xuint timeout_usec )
{
    //_xperipherals_uart_1__bit_period_1 = (1 * REFERENCE_CLOCK_FREQUENCY) / (2 * baud_rate);
    _xperipherals_uart_1__period = (2 * REFERENCE_CLOCK_FREQUENCY) / (2 * baud_rate);
}

#if XPERIPHERALS_UART_1__SUPPORT_TX

void xperipherals_uart_1__write_byte( xbyte data )
{
	// Serial: START ................ 1 Byte of Data ............... STOP
	// Output: LLLLL 11111 22222 33333 44444 55555 66666 77777 88888 HHHHH
	// Timing: A     B     C     D     E     F     G     H     I     J
	
    timer _xperipherals_uart_1__timer;
    int time; _xperipherals_uart_1__timer :> time;

   	_xperipherals_uart_1__port_txd <: 0;
    time += _xperipherals_uart_1__period;
    _xperipherals_uart_1__timer when timerafter(time) :> void; // A

    #pragma loop unroll
    for( int i = 0; i < 8; ++i ) // B,C,D,E,F,G,H,I
    {
        _xperipherals_uart_1__port_txd <: ((unsigned int)data & 1); data >>= 1;
        time += _xperipherals_uart_1__period;
        _xperipherals_uart_1__timer when timerafter(time) :> void;
    }

    _xperipherals_uart_1__port_txd <: 1;
    time += _xperipherals_uart_1__period;
    _xperipherals_uart_1__timer when timerafter(time) :> void; // J
}

void xperipherals_uart_1__begin_write( xbyte data )
{
    _xperipherals_uart_1__wdata = data;
    _xperipherals_uart_1__count = 0;
    _xperipherals_uart_1__timer :> _xperipherals_uart_1__time;
    _xperipherals_uart_1__port_txd <: 0;
    _xperipherals_uart_1__time += _xperipherals_uart_1__period;
    _xperipherals_uart_1__wbusy = TRUE;
}

select xperipherals_uart_1__continue_wr( int& done )
{
    case _xperipherals_uart_1__wbusy => _xperipherals_uart_1__timer when timerafter(_xperipherals_uart_1__time) :> void:

        if( _xperipherals_uart_1__count == 0 )
        {
            _xperipherals_uart_1__port_txd <: ((unsigned int)_xperipherals_uart_1__wdata & 1);
            _xperipherals_uart_1__wdata >>= 1;
            _xperipherals_uart_1__time += _xperipherals_uart_1__period;
            ++_xperipherals_uart_1__count;
            done = FALSE;
        }
        else if( _xperipherals_uart_1__count <= 8 )
        {
            _xperipherals_uart_1__port_txd <: ((unsigned int)_xperipherals_uart_1__wdata & 1);
            _xperipherals_uart_1__wdata >>= 1;
            _xperipherals_uart_1__time += _xperipherals_uart_1__period;
            ++_xperipherals_uart_1__count;
            done = FALSE;
        }
        else if( _xperipherals_uart_1__count <= 20 )
        {
            _xperipherals_uart_1__port_txd <: 1;
            _xperipherals_uart_1__time += _xperipherals_uart_1__period;
            ++_xperipherals_uart_1__count;
            done = _xperipherals_uart_1__count == 20;
            _xperipherals_uart_1__wbusy = !done;
        }
        break;
}

#endif

#if XPERIPHERALS_UART_1__SUPPORT_RX

void xperipherals_uart_1__read_byte( xbyte& data )
{
    timer _xperipherals_uart_1__timer;
    xbyte bit; int time;

    // Wait for START bit (Step A)
    _xperipherals_uart_1__port_rxd when pinseq(0) :> void;
    _xperipherals_uart_1__timer :> time;
    time += _xperipherals_uart_1__period / 2;

    // Sample 8 bits (Steps B,C,D,E,F,G,H,I)
    #pragma loop unroll
    for( int i = 0; i < 8; ++i )
    {
        time += _xperipherals_uart_1__period;
        _xperipherals_uart_1__timer when timerafter(time) :> void;
        _xperipherals_uart_1__port_rxd :> bit; data = (data>>1) + (bit<<7);
    }

    // Wait for STOP bit to pass ...
    time += _xperipherals_uart_1__period;
    _xperipherals_uart_1__timer when timerafter(time) :> void;
}

void xperipherals_uart_1__begin_read( void )
{
    _xperipherals_uart_1__count = 0;
    _xperipherals_uart_1__timer :> _xperipherals_uart_1__time;
    _xperipherals_uart_1__time += _xperipherals_uart_1__period;
    _xperipherals_uart_1__rbusy = TRUE;
}

select xperipherals_uart_1__continue_rd( int& done, unsigned char& data )
{
    case _xperipherals_uart_1__rbusy => _xperipherals_uart_1__timer when timerafter(_xperipherals_uart_1__time) :> void:

        if( _xperipherals_uart_1__count == 0 )
        {
            _xperipherals_uart_1__time += _xperipherals_uart_1__period;
            ++_xperipherals_uart_1__count;
            done = FALSE;
        }
        else if( _xperipherals_uart_1__count <= 8 )
        {
            _xperipherals_uart_1__time += _xperipherals_uart_1__period;
            ++_xperipherals_uart_1__count;
            done = FALSE;
        }
        else if( _xperipherals_uart_1__count <= 20 )
        {
            _xperipherals_uart_1__time += _xperipherals_uart_1__period;
            ++_xperipherals_uart_1__count;
            done = _xperipherals_uart_1__count == 20;
            _xperipherals_uart_1__rbusy = FALSE;
       }
        break;
}

#endif

#endif