Texas Instruments TMS320C64x DSP Benutzerhandbuch

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Example 2: Noncontinuous Frame Display for 525/60 Format
Video Port Configuration Examples
A-10
SPRU629
A.2 Example 2: Noncontinuous Frame Display for 525/60 Format
This is an example that explains how to configure the video port for 8-bit
BT.656 noncontinuous frame display for 525/60 format. See ITU–R BT.656–4
and video port specification (Figures 4–11, 4–33, 4–34, and Table 4–37) for
more details on 525/60 format. For simplicity, this example does not contain
any margins;  that is, both vertical and horizontal offsets are zero. In other
words, both active area and image area are the same.
/**********************************************************/
/* Display parameter definitions based on 525/60 format   */
/**********************************************************/
/* ––––––––––––––––– */
/* Define frame size */
/* ––––––––––––––––– */
#define VD_FRM_WIDTH
858 /* no of pixels per frame line     */
                    
    /* including horizontal blanking   */
#define VD_FRM_HEIGHT
525 /* total noof lines per frame      */
#define VD_FRM_SIZE
(VD_FRM_WIDTH * VD_FRM_HEIGHT)
/* ––––––––––––––––––– */
/* Horizontal blanking */
/* ––––––––––––––––––– */
#define VD_HBLNK_START
720 /* starting location of EAV        */
#define VD_HBLNK_STOP
856 /* starting location of SAV        */
#define VD_HBLNK_SIZE
(VD_HBLNK_STOP – VD_HBLNK_START +
 2/*EAV*/) /* (138) EAV, SAV inclusive */
/* –––––––––––––––––––––––––––– */
/* Vertical blanking for field1 */
/* –––––––––––––––––––––––––––– */
#define VD_VBLNK_XSTART1
720 /* pixel on which VBLNK active     */
                        
    /* edge occurs for field1          */
#define VD_VBLNK_YSTART1
1   /* line on which VBLNK active      */
                        
    /* edge occurs for field1          */
#define VD_VBLNK_XSTOP1
720 /* pixel on which VBLNK inactive   */
                       
    /* edge occurs for field1          */
#define VD_VBLNK_YSTOP1
20  /* line on which VBLNK inactive    */
                       
    /* edge occurs for field1          */
/* –––––––––––––––––––––––––––– */
/* Vertical blanking for field2 */
/* –––––––––––––––––––––––––––– */
#define VD_VBLNK_XSTART1
360 /* pixel on which VBLNK active     */
                        
    /* edge occurs for field2          */
#define VD_VBLNK_YSTART1
263 /* line on which VBLNK active      */
                         
    /* edge occurs for field2          */
#define VD_VBLNK_XSTOP1
360 /* pixel on which VBLNK inactive   */
                        
    /* edge occurs for field2          */
#define VD_VBLNK_YSTOP1
283 /* line on which VBLNK inactive    */
                        
    /* edge occurs for field2          */