dve_ccir_vtg.v

全电视信号编码器

// Lines, where the color is enabled
`define LINE_NUMBER_6               (10'd6 - 10'd1)
`define LINE_NUMBER_7               (10'd7 - 10'd1)
`define LINE_NUMBER_17              (10'd17 -10'd1)
`define LINE_NUMBER_24              (10'd24 -10'd1)
`define LINE_NUMBER_260             (10'd260-10'd1)             
`define LINE_NUMBER_261             (10'd261-10'd1)             
`define LINE_NUMBER_270             (10'd270-10'd1)             
`define LINE_NUMBER_282             (10'd282-10'd1)             
`define LINE_NUMBER_310             (10'd310-10'd1)
`define LINE_NUMBER_311             (10'd311-10'd1)
`define LINE_NUMBER_319             (10'd319-10'd1)
`define LINE_NUMBER_320             (10'd320-10'd1)
`define LINE_NUMBER_336             (10'd336-10'd1)
`define LINE_NUMBER_523             (10'd523-10'd1)
`define LINE_NUMBER_622             (10'd622-10'd1)
`define LINE_NUMBER_623             (10'd623-10'd1)
// For the ortogonal frame structure compensation in the PAL mode
`define PAL_MIDDLE_LINE             (10'd313-10'd1)  // 
`define PAL_LAST_LINE               (10'd625-10'd1)  //           
`define PAL_LINES_PER_FRAME         (10'd625-10'd1)
`define NTSC_LINES_PER_FRAME        (10'd525-10'd1)


`define PAL_HALFLINE_SAMPLES  		(10'd864-10'd1)   // PAL HALFLINE SAMPLES 64us/2
`define PAL_ENDOFSYNC_LINE          (10'd128-10'd1)   // normal 4.70 us= 127 SAMPLES @ 27MHz
`define PAL_ENDOFSYNC_EQU           (10'd64 -10'd1)   // equlization 2.35 us= 64  SAMPLES @ 27MHz
`define PAL_ENDOFSYNC_SERR          (10'd737-10'd1)   // serration 27.3 us= 737 SAMPLES @ 27MHz

`define NTSC_HALFLINE_SAMPLES       (10'd858-10'd1)   // NTSC HALFLINE SAMPLES 63.5(5)/2
`define NTSC_ENDOFSYNC_LINE         (10'd128-10'd1)   // normal 4.7 us = 127 SAMPLES @ 27MHz
`define NTSC_ENDOFSYNC_EQU          (10'd62 -10'd1)   // equlization 2.3 us equalization 4.70 us= 62 PAL SAMPLES 
`define NTSC_ENDOFSYNC_SERR         (10'd729-10'd1)   // serration 27.1 us= 729 SAMPLES @ 27MHz

// Pipelining is taken into account
// Values for the colorburst insertion
`define PAL_CBURST_ON               (10'd152-10'd0)  // PAL:5.6 us @ 17.734475 MHz
`define PAL_CBURST_OFF              (10'd214-10'd0)  // PAL: 5.6 us + 10 FSc cycles @ 4.43       
`define NTSC_CBURST_ON              (10'd144-10'd0)  // NTSC:19 FSc cycles @3.57
`define NTSC_CBURST_OFF             (10'd212-10'd0)  // NTSC:28 FSc cycles @3.57 
// Video blanking intervals for PAL and NTSC modes
`define PIPELINE_DELAY              (11'd0)          // pipeline delay
`define PAL_VIDEO_ENABLE            (11'd284 +`PIPELINE_DELAY-11'd1)
`define PAL_VIDEO_DISABLE           (11'd1688+`PIPELINE_DELAY-11'd1)
`define NTSC_VIDEO_ENABLE           (11'd252 +`PIPELINE_DELAY-11'd1) 
`define NTSC_VIDEO_DISABLE          (11'd1674+`PIPELINE_DELAY-11'd1)

`define COLORBAR_WIDTH_PAL          (8'd176 - 8'd1)
`define COLORBAR_WIDTH_NTSC         (8'd176 - 8'd1)
// -----------------------------------------------------------------------------
//
// Pixel counter counts upto half line last sample value .....
//
// -----------------------------------------------------------------------------
always @(posedge sclk)
 if (!srst_n || last_line_sample) pixel_counter <= {PIXEL_COUNTER_WIDTH{1'b0}};
 else pixel_counter <= pixel_counter + {{PIXEL_COUNTER_WIDTH-1{1'b0}},1'b1};

// -----------------------------------------------------------------------------
//
// Last halfline sample comparator.....
//
// -----------------------------------------------------------------------------
assign last_line_sample = (coding_ntsc) ? (pixel_counter == `NTSC_HALFLINE_SAMPLES) :
	(pixel_counter == `PAL_HALFLINE_SAMPLES);


assign middle_of_frame = (line_counter == `PAL_MIDDLE_LINE);
assign end_of_frame = (line_counter == `PAL_LAST_LINE);

// -----------------------------------------------------------------------------
//
// HALFLINE counter counts upto the last halfline number ...
//
// -----------------------------------------------------------------------------
always @(posedge sclk)
 if (~srst_n | last_halfline & last_line_sample) halfline_counter <= {HALFLINE_COUNTER_WIDTH{1'b0}};
 else if (last_line_sample) halfline_counter <= halfline_counter + {{PIXEL_COUNTER_WIDTH-1{1'b0}},1'b1};


// -----------------------------------------------------------------------------
//
// LINE counter counts upto the last line number in the field
//
// -----------------------------------------------------------------------------
always @(posedge sclk)
 if (~srst_n | last_line_sample & last_line & ~sm_first_halfline_reg) 
       line_counter <= {LINE_COUNTER_WIDTH{1'b0}}; 
 else if (last_line_sample & ~sm_first_halfline_reg) 
       line_counter <= line_counter + {{LINE_COUNTER_WIDTH-1{1'b0}},1'b1};

assign last_line = (coding_ntsc) ?  (line_counter == `NTSC_LINES_PER_FRAME) :
       (line_counter == `PAL_LINES_PER_FRAME);

 
// -----------------------------------------------------------------------------
//
// The last halfline number comparator ....
//
// -----------------------------------------------------------------------------
assign last_halfline = (halfline_counter == last_halfline_reg);	 

// -----------------------------------------------------------------------------
//
// .... The halfline register dynamically stores the current value of the last
//      halfline number ....
//
// -----------------------------------------------------------------------------
always @(posedge sclk)
 begin
  if (~srst_n | ((sm_sc_serr_reg | sm_sc_preequ_reg | sm_sc_postequ_reg) & ~coding_ntsc))
                last_halfline_reg <= `PAL_SYNPULSE_NUMBER;
  else if ((sm_sc_preequ_reg | sm_sc_postequ_reg | sm_sc_serr_reg) & coding_ntsc) 
                last_halfline_reg <= `NTSC_SYNPULSE_NUMBER;
  else if (sm_sc_linespace_reg & ~coding_ntsc)
                last_halfline_reg <= `PAL_HALFLINE_NUMBER;
  else last_halfline_reg <= `NTSC_HALFLINE_NUMBER;  	 
 end
// -----------------------------------------------------------------------------
// PREEQUALIZATION, SERRATION, POSTEQUALIZATION and FIELD SPACE state machine
// ONE-HOT implementation
// Reset state: SERRATION (beginning of the next field)
// -----------------------------------------------------------------------------
always @(posedge sclk)
 begin
  sm_sc_preequ_reg <= srst_n & ((~sm_sc_preequ_reg & sm_sc_linespace_reg & last_line_sample 
    & last_halfline) | (sm_sc_preequ_reg & ~(last_line_sample & last_halfline)));
  sm_sc_serr_reg   <= ~srst_n | (srst_n & ~sm_sc_serr_reg & sm_sc_preequ_reg & last_line_sample
    & last_halfline) | (srst_n & sm_sc_serr_reg & ~(last_line_sample & last_halfline));
  sm_sc_postequ_reg<= srst_n & ((~sm_sc_postequ_reg & sm_sc_serr_reg & last_line_sample 
    & last_halfline) | (sm_sc_postequ_reg & ~(last_line_sample & last_halfline)));                  	 
  sm_sc_linespace_reg <= srst_n & (( ~sm_sc_linespace_reg & sm_sc_postequ_reg & last_line_sample 
    & last_halfline) | (sm_sc_linespace_reg & ~(last_line_sample & last_halfline)));
 end
	 
// -----------------------------------------------------------------------------
//
// ..... HALF-LINE length control state machine. Required only in the PAL mode .....
//
// -----------------------------------------------------------------------------
always @(posedge sclk)
 sm_first_halfline_reg <= ~srst_n | (~sm_first_halfline_reg & last_line_sample) |
                       (sm_first_halfline_reg & ~last_line_sample);


// -----------------------------------------------------------------------------
//
// ..... ODD/EVEN frame control state machine
//
// -----------------------------------------------------------------------------
always @(posedge sclk)
begin
 sm_first_frame_reg <= ~srst_n | 
     (~sm_first_frame_reg & last_line_sample & last_line & ~sm_first_halfline_reg) |
     (sm_first_frame_reg & ~(last_line_sample & last_line & ~sm_first_halfline_reg));

 sm_fields_one_to_four_reg <= ~srst_n |
     (~sm_fields_one_to_four_reg & last_line_sample & last_line 
      & ~sm_first_halfline_reg & ~sm_first_frame_reg)|
     (sm_fields_one_to_four_reg 
      & ~(last_line_sample & last_line & ~sm_first_halfline_reg & ~sm_first_frame_reg));
end

// -----------------------------------------------------------------------------
// Active at the time of the first halfline sample every odd halfline at the active space or
// every halfline at the time of serration and equalization pulses
//
// -----------------------------------------------------------------------------

assign start_sync = (sm_sc_linespace_reg & ~sm_first_halfline_reg & last_line_sample) | 
// Always generated to start the preequalisation phase
(sm_sc_linespace_reg & last_halfline & last_line_sample) |
// For all the series of preequalisation/serration/postequ. 
(sm_sc_preequ_reg | sm_sc_serr_reg) & last_line_sample |
// For all synchrostarts at the postequalisation pulses
(sm_sc_postequ_reg & ~last_halfline & last_line_sample) |
// The first synchrostart at the linespace
(sm_sc_postequ_reg & last_halfline & ~sm_first_halfline_reg & last_line_sample);

// Depending on the selected coding standard, signals the end of sync 
assign end_sync   =  end_of_sync_line & sm_sc_linespace_reg & sm_first_halfline_reg | 
                     end_of_sync_equ & (sm_sc_preequ_reg | sm_sc_postequ_reg) |
                     end_of_sync_serr & sm_sc_serr_reg;
 
// -----------------------------------------------------------------------------
// The "end of sync tip" comparators
// -----------------------------------------------------------------------------
assign end_of_sync_line = (coding_ntsc) ? 
        (pixel_counter==`NTSC_ENDOFSYNC_LINE):(pixel_counter==`PAL_ENDOFSYNC_LINE); 
assign end_of_sync_serr = (coding_ntsc) ?
        (pixel_counter==`NTSC_ENDOFSYNC_SERR):(pixel_counter==`PAL_ENDOFSYNC_SERR); 
assign end_of_sync_equ  = (coding_ntsc) ?
        (pixel_counter==`NTSC_ENDOFSYNC_EQU):(pixel_counter==`PAL_ENDOFSYNC_EQU); 
 
// -----------------------------------------------------------------------------
// SYNC TIP state machine (one-hot implementation)
// -----------------------------------------------------------------------------
// In PAL mode the slope is equal to 0.2us+/-0.1us  4 samples
// In NTSC 0.14us+/-0.1 us	
// Necessary to have two different LUTs to express different sync values and travel
// points
always @(posedge sclk)
begin
 csync_out <= srst_n & ((csync_out & ~start_sync) | (~csync_out & end_sync));
 vsync_out <= srst_n & ((vsync_out & ~(sm_sc_preequ_reg & last_line_sample
    & last_halfline)) | (~vsync_out & last_line_sample & last_halfline)); 
 sm_hsync_reg <= srst_n & ( sm_hsync_reg & ~(~sm_first_halfline_reg & last_line_sample) |
    ~sm_hsync_reg & end_of_sync_line);
end

assign hsync_out = sm_hsync_reg;
// -----------------------------------------------------------------------------
// SYNC TIP state machine (one-hot implementation)
// -----------------------------------------------------------------------------
// In PAL mode the slope is equal to 0.2us+/-0.1us  4 samples
// In NTSC 0.14us+/-0.1 us	
// Necessary to have two different LUTs to express different sync values and travel
// points

always @(sm_tip_state or start_sync or end_sync)
    case (sm_tip_state)
     `SYNC_TIP_IDLE :   if (start_sync) sm_tip_next=`SYNC_TIP_LEADER; 
	                   else  sm_tip_next=`SYNC_TIP_IDLE; 
	 `SYNC_TIP_LEADER:  if (sm_tipstat == `SYNC_STAT_ACTIVE) sm_tip_next=`SYNC_TIP_ZEROH;
		               else  sm_tip_next = `SYNC_TIP_IDLE;
	 `SYNC_TIP_ZEROH:   if (sm_tipstat == `SYNC_STAT_ACTIVE) sm_tip_next=`SYNC_TIP_TRAILER;
		               else  sm_tip_next = `SYNC_TIP_LEADER; 
	 `SYNC_TIP_TRAILER:	if (sm_tipstat == `SYNC_STAT_ACTIVE) sm_tip_next=`SYNC_TIP_LEVEL;
		               else  sm_tip_next = `SYNC_TIP_ZEROH;  
	 `SYNC_TIP_LEVEL:	if (end_sync) sm_tip_next=`SYNC_TIP_TRAILER;
		               else sm_tip_next=`SYNC_TIP_LEVEL;
	 default: 	        sm_tip_next=`SYNC_TIP_IDLE;
    endcase