
// Example C Code for setting up WSS/CGMS Line Mode Registers
//
// Load C-RAM
//
// NTSC WSS/CGMS Line Mode setup for line 20 of both fields
I2CWriteByte(TVP5154A, 0xEC, 0x09); // line 20 field 1 (0xEC), mode bits = 0x09
I2CWriteByte(TVP5154A, 0xED, 0x09); // line 20 field 2 (0xED), mode bits = 0x09
I2CWriteByte(TVP5154A, 0xCB, 0x4E); // Set Pixel Alignment [7:0]to 0x4E
I2CWriteByte(TVP5154A, 0xCC, 0x00); // Set Pixel Alignment [9:8]to 0x00
// PAL WSS/CGMS Line Mode setup for line 23 (source input) of both fields.
// PAL line numbering has 3 line offset so the Line 26 line mode registers are used.
I2CWriteByte(TVP5154A, 0xF8, 0x08); // line 26 field 1 (0xF8), mode bits = 0x08
I2CWriteByte(TVP5154A, 0xF9, 0x08); // line 26 field 2 (0xF9), mode bits = 0x08
I2CWriteByte(TVP5154A, 0xCB, 0x4E); // Set Pixel Alignment [7:0]to 0x4E
I2CWriteByte(TVP5154A, 0xCC, 0x00); // Set Pixel Alignment [9:8]to 0x00
Line Mode Registers
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relative to actual PAL line numbers. For PAL systems, the Line Mode register for line “N+3” must be used
to configure a data service transmitted on line N of the input source. Figure 3 shows example C code for
configuring WSS/CGMS data services for NTSC and PAL. Included in this example is an I2C write to the
Pixel Alignment Registers (CBh-CCh), which define the horizontal position where data slicing begins. The
value used (4Eh) is recommended for all data services.
Table 3. Line Mode Configuration Bits for Supported Modes
Line Mode Register Name Video Line Number Description
(D0h-FCh) Bits [3:0]
0000b WST SECAM 6-23 (field 1, 2) Teletext, SECAM
0001b WST PAL B 6-22 (field 1, 2) Teletext, PAL, System B
0010b WST PAL C 6-22 (field 1, 2) Teletext, PAL, System C
0011b WST, NTSC B 10-21 (field 1, 2) Teletext, NTSC, System B
0100b NABTS, NTSC C 10-21 (field 1, 2) Teletext, NTSC, System C
0101b NABTS, NTSC D 10-21 (field 1, 2) Teletext, NTSC, System D (Japan)
0110b CC, PAL/SECAM 22 (field 1, 2) Closed caption PAL/SECAM
0111b CC, NTSC 21 (field 1, 2) Closed caption NTSC
1000b WSS/CGMS, PAL/SECAM 23 (field 1, 2) Wide-screen signal, PAL/SECAM
1001b WSS/CGMS, NTSC 20 (field 1, 2) Wide-screen signal, NTSC
1010b VITC, PAL/SECAM 6-22 Vertical interval timecode, PAL/SECAM
1011b VITC, NTSC 10-20 Vertical interval timecode, NTSC
1100b VPS, PAL 16 Video program system, PAL
1101b EPG/Gemstar Electronic program guide - Custom mode
1110b x x Reserved
1111b Active Video Active Video Active video/full field
Figure 3. Line Mode Setup for WSS/CGMS
6TVP5154A VBI Quick Start SLEA104–July 2010
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