sensor12bits.v

module	sensor12bits (MCLK,	// Master clock
						MRST,	// Master Reset - active low
						ARO,	// Array read Out.
						ARST,	// Array Reset. Active low
						OE,	// output enable active low
						SCL,	// I2C clock
						SDA,	// I2C data
						OFST,	// I2C address ofset by 2: for simulation 0 - still mode, 1 - video mode.
						D,		// [11:0] data output
						DCLK,	// Data output clock
						BPF,	// Black Pixel Flag
						HACT,	// Horizontal Active
						VACT, // Vertical Active
                  VACT1);
input			MCLK,	// Master clock
				MRST,	// Master Reset - active low
				ARO,	// Array read Out.
				ARST,	// Array Reset. Active low
				OE,		// output enable active low
				SCL;	// I2C clock
inout			SDA;	// I2C data
input			OFST;	// I2C address ofset by 2: for simulation 0 - still mode, 1 - video mode.

output	[11:0]	D;		// data output
output			DCLK,	// Data output clock
				BPF,	// Black Pixel Flag
				HACT,	// Horizontal Active
				VACT,	// Vertical Active
            VACT1; // 1-clock VACT
parameter ramp	=	1;	// 1 - ramp, 0 - random
parameter lline	=	192; //	1664;//	line duration in clocks
parameter ncols	=	66; //58; //56; // 129; //128;	//1288;
parameter nrows	=	18; // 16;	//	1032;
parameter nrowb =	1;	// number of "blank rows" from vact to 1-st hact
parameter nrowa	=	1;	// number of "blank rows" from last hact to end of vact
parameter nAV	=	24;	//240;	// clocks from ARO to VACT (actually from en_dclkd)
parameter nbpf	=	20;	//16; // bpf length
parameter ngp1	=	8;	// bpf to hact
parameter nVLO	=	1;	// VACT=0 in video mode (clocks)
//parameter tMD	=	14;	//
//parameter tDDO	=	10;	//	some confusion here - let's assume that it is from DCLK to Data out
parameter tMD	=	4;	//
parameter tDDO	=	2;	//	some confusion here - let's assume that it is from DCLK to Data out
parameter tDDO1=	5;


parameter	s_stop=		0;
parameter	s_preVACT=	1;
parameter	s_firstline=2;
parameter	s_BPF=		3;
parameter	s_preHACT=	4;
parameter	s_HACT=		5;
parameter	s_afterHACT=6;
parameter	s_lastline=	7;
parameter	s_frame_done=8;

parameter	t_preVACT=	nAV;			// 240
parameter	t_firstline=nrowb*lline+1;	// 1664
parameter	t_BPF=		nbpf;			// 16
parameter	t_preHACT=	ngp1;			// 8
parameter	t_HACT=		ncols;			// 1288
parameter	t_afterHACT=lline-nbpf-ngp1-ncols;	// 352
parameter	t_lastline=	nrowa*lline+1;	// 1664


  reg	[15:0]	sensor_data[0:4095]; // up to 64 x 64 pixels
//    $readmemh("sensor.dat",sensor_data);



reg			c;		// internal data out clock
//reg		[9:0]	id;		// internal pixel data (sync do DCLK)
//wire	[9:0]	nxt_d;	// will be calculated later - next pixel data
reg				stopped;
wire	#1		stoppedd=stopped;
reg				ibpf, ihact, ivact, ivact1;
reg				arst1;	//
reg		[11:0]	col;	// current row
reg		[11:0]	row;	// current column;
reg		[3:0]	state;
reg		[15:0]	cntr;
wire	[11:0]	cold;
wire	[11:0]	rowd;
wire	[3:0]	stated;
wire	[15:0]	cntrd;
wire			NMRST=!MRST;

parameter new_bayer=0; // 0 - old (16x16), 1 - new (18x18)

wire	[5:0] row_index=row[5:0]-new_bayer;
wire	[5:0] col_index=col[5:0]-new_bayer;


// random
integer 		seed;
integer			r;
reg				c_rand;
reg		[11:0]	d_rand;



assign		#1	cold=	col;
assign		#1	rowd=	row;
assign		#1	stated=	state;
assign		#1	cntrd=	cntr;



//assign	#tDDO	D	=  OE?	{10{1'bz}}:	((ihact || ibpf)?	((ramp)?(col[9:0] + row[9:0]):(d_rand)): 10'b0); // just test pattern
//assign	#tDDO	D	=  OE?	{10{1'bz}}:	((ihact || ibpf)?	((ramp)?(col[9:0] + row[9:0]):(sensor_data[{row_index[5:0],col_index[5:0]}])): 10'b0); // just test pattern
//assign	#tDDO	D	=  OE?	{12{1'bz}}:	((ihact || ibpf)?	((ramp)?(col[11:0] + row[11:0]):(sensor_data[{row_index[5:0],col_index[5:0]}])): 12'b0); // just test pattern
wire [11:0] strange_value=sensor_data[{row_index[5:0],col_index[5:0]}];
assign	#tDDO	D	=  OE?	{12{1'bz}}:	((ihact || ibpf)?	((ramp)?({row[11:8],8'h0} + col[11:0]):(strange_value)): 12'b0); // just test pattern
//assign	#tDDO	BPF	= ibpf;
//assign	#tDDO	HACT= ihact;
//assign	#tDDO	VACT= ivact;
assign	#tDDO1	BPF	= ibpf;
assign	#tDDO1	HACT= ihact;
assign	#tDDO1	VACT= ivact;
assign	#tDDO1	VACT1= ivact && !ivact1;
assign			DCLK= c;

initial begin
//parameter ramp	=	1;	// 0 - ramp, 1 - random
//parameter lline	=	192; //	1664;//	line duration in clocks
//parameter ncols	=	58; //56; // 129; //128;	//1288;
//parameter nrows	=	16;	//	1032;

	$display ("sensor parameters");
	$display ("    -- ramp  = %d (0 - random, 1 - ramp)",ramp);
	$display ("    -- lline = %d (line duration in clocks)",lline);
	$display ("    -- ncols = %d (numer of clocks in HACT)",ncols);
	$display ("    -- nrows = %d (number of rows)",nrows);
	$display ("    -- t_afterHACT = %d ",t_afterHACT);
	$display ("    -- t_preHACT = %d ",t_preHACT);
	$display ("    -- new_bayer = %d ",new_bayer);

//  reg	[15:0]	sensor_data[0:4095]; // up to 64 x 64 pixels
    $readmemh("sensor.dat",sensor_data);



	c=0;
//	{ibpf,ihact,ivact}=0;
	stopped=1;
	arst1=	0;
	seed=	1;
	d_rand=	0;
//	row=0;
//	col=0;

end
always @ (NMRST) begin
	c=0;
//	{ibpf,ihact,ivact}=0;
	stopped=1;
	arst1=0;
//	row=0;
//	col=0;
end

always begin
	@ (posedge MCLK) begin
		#tMD	c = !stoppedd;
		end
	@ (negedge MCLK) begin
		#tMD	c = 1'b0;
	end
end

always @ (posedge MCLK) begin
	#1	stopped= !arst1 || (stoppedd && !ARO) ;
	#1	arst1=ARST;
end

always @ (posedge c) ivact1 = ivact;
always @ (posedge stoppedd or posedge c) begin
	if (stoppedd) begin
		{ibpf,ihact,ivact}=0;
		row=0;
		col=0;
//		id=0;
		state=0;
		cntr=0;
	end else if (|cntrd != 0) begin
		#1 cntr=cntrd-1;
		if (BPF || HACT) col=cold+1;
	end else begin
		case (stated)
		s_stop: begin
				cntr=	t_preVACT-1;
				state=	s_preVACT;
			end
		s_preVACT: begin
				ivact=	1'b1;
				cntr=	t_firstline-1;
				state=	s_firstline;
			end
 		s_firstline: begin
				ibpf=	1'b1;
				col=	0;
				row=	0;
				cntr=	t_BPF-1;
				state=	s_BPF;
			end
		s_BPF: begin
				ibpf=	1'b0;
				cntr=	t_preHACT-1;
				state=	s_preHACT;
			end
		s_preHACT: begin
				ihact=	1'b1;
				col=	0;
				cntr=	t_HACT-1;
				state=	s_HACT;
			end
		s_HACT: begin
				ihact=	1'b0;
				row=	rowd+1;
				cntr=	t_afterHACT-1;
				state=	s_afterHACT;
			end
		s_afterHACT:
			if (rowd == nrows) begin
				cntr=	t_lastline-1;
				state=	s_lastline;
			end else begin
				ibpf=	1'b1;
				col=	0;
				cntr=	t_BPF-1;
				state=	s_BPF;
			end
		s_lastline: begin
				ivact=	1'b0;
				state=	s_frame_done;
				cntr=nVLO;
			end
		s_frame_done: if (OFST) begin
				ivact=	1'b1;
				cntr=	t_firstline-1;
				state=	s_firstline;
			end
		endcase

	end
// random data
    seed=$random(seed);
    r=(seed & 'h7fff);
	r=(r * r) >> 20; // 10 bits
	c_rand=seed>>16; // sign
	d_rand=c_rand?(D+(((1023-d_rand)*r)>>10)):(d_rand-((d_rand*r)>>10));
end



endmodule