Doremi HDG-20 - Manual (Page 19)

7 Appendix A: CEA-608 Closed Captioning
The CEA-608 closed captioning sent on SDI stream is SMPTE 334 compliant. Two bytes are
sent each frame in ancillary data, with a cycle of 251 frames:
Frame 0 : 0x94, 0xae => Clear Buffer
Frame 1 : 0x94, 0xae => Clear Buffer
Frame 2 : 0x94, 0x20 => start pop up
Frame 3 : 0x94, 0x20 => start pop up
Frame 4 : 0x94, 0x7a => move cursor to row 15 column 20
Frame 5 : 0x94, 0x7a => move cursor to row 15 column 20
Frame 6 : 0x94, 0xa2 => move over 2 more columns
Frame 7 : 0x94, 0xa2 => move over 2 more columns
Frame 8 : 0xC4, 0xC8 => Write “H” , Write “D”
Frame 9 : 0xC9, 0x20 => Write “G” , Write “ ”
Frame 10 : 0x31, 0xB0 => Write “1” , Write “0”
Frame 11 : 0x94, 0x2c => Clear current Caption
Frame 12 : 0x94, 0x2c => Clear current Caption
Frame 13 : 0x80, 0x80 => No operation
Frame 14 : 0x80, 0x80 => No operation
Frame 15 : 0x94, 0x2f => Display Caption
Frame 16 : 0x94, 0x2f => Display Caption
Frame 17–119: 0x80, 0x80 => No operation
Frame 120
: 0x94, 0xae => Clear Buffer
Frame 121 : 0x94, 0xae => Clear Buffer
Frame 122 : 0x94, 0x20 => start pop up
Frame 123 : 0x94, 0x20 => start pop up
Frame 124 : 0x94, 0xf7 => move cursor to row 15 column 12, and write underlined
Frame 125 : 0x94, 0xf7 => move cursor to row 15 column 12, and write underlined
Frame 126 : 0x94, 0xa2 => move over 2 more columns
Frame 127 : 0x94, 0xa2 => move over 2 more columns
Frame 128 : 0xC4, 0xC8 => Write “D” , Write “o”
Frame 129 : 0xC9, 0x20 => Write “r” , Write “e”
Frame 130 : 0x31, 0xB0 => Write “m” , Write “i”
Frame 131 : 0x94, 0x2c => Clear current Caption
Frame 132 : 0x94, 0x2c => Clear current Caption
Frame 133 : 0x80, 0x80 => No operation
Frame 134 : 0x80, 0x80 => No operation
Frame 135 : 0x94, 0x2f => Display Caption
Frame 136 : 0x94, 0x2f => Display Caption
Frame 137–250 : 0x80, 0x80 => No operation
Each control code is transmitted twice, as requested in CEA- 608 specifications.
HDG.OM.000248.DRM Page 19 of 24 Version 1.6
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