TMS320AV7110 datasheet(49/131 Pages) TI

49 / 131 page

DSP

TMS320AV7110

Revision 3.1

10/08/99 22:18

Page 49

• The clock period of the Teletext data should be 144nsec ± 5%

• Teletext transmission in DVB is covered by document ETS 300 472

• The Teletext bit rate is 6.9375MHz ± 100ppm.

• Teletext data starts at 10.2 µSec after the leading edge of the horizontal synchronization

pulse

• Teletext insertion conforms to the EBU Teletext spec ITU-R rec. 653 system B

• Each Teletext line contains 45 bytes of data

• 16 bits of clock run in, generated in the ‘AV7110

• 43 bytes of data from the PES payload

• Teletext is only inserted in PAL mode

9.2.2 WSS insertion into CVBS

• WSS data is inserted into TV line 23 only

• WSS transmission is specified in ESTI standard 300 294, ‘Television systems 625-line television

wide screen signaling (WSS)

• WSS is only inserted in PAL mode.

• WSS is only inserted into analog CVBS

• WSS data clock frequency is 5MHz ± 5%

9.2.3 Insertion mode

An API is provided for the user to select if the Teletext signal is to be inserted internally or externally.

WSS can only be inserted internally. Teletext data resolution in the composite signal for internal

insertion and on the TEXTEN pin for external insertion is 27MHz.

Internal insertion: The Teletext and WSS data are inserted by the on-chip NTSC/PAL encoder into

the analog CVBS signal.

External insertion: The Teletext signal is externally inserted via an external video encoder that has

Teletext insertion capability. To allow this mode of operation, the Teletext signal is always output on

the TEXTEN pin. The video signal on the digital out (YCOUT[7:0]) and the Teletext signal on

TEXTEN are compliant with Philips™ SA7182/3 digital video encoder’s input requirements.

Note that the external insertion option is not available if the 32-bit EBI mode is used due to pin

multiplexing. Figure 15 shows external insertion of the Teletext signal.

‘AV7110

TEXTEN

YCOUT[7:0]

YCCLK

External Video

encoder

(w/Teletext in)

e.g., Philips’

SAA7182/3

CVBS

Figure 15. External Insertion of Teletext signal

9.3 Closed Caption, Extended Data Services, and Video Aspect Ratio

Identification Signal Insertion (NTSC mode only)

Closed Caption (CC) and Extended Data Services (EDS) are transmitted as picture layer user data.

The video decoder extracts the CC and EDS information from the video bit-stream and sends it to the

NTSC/PAL encoder module.

The video decoder also extracts the aspect ratio from the bit-stream and sends it to the ARM which

prepares data according to the Video Aspect Ratio Identification Signal (VARIS) standard, EIAJ CPX -

1204. The ARM then sends the code to the NTSC/PAL encoder to insert CC data into the analog or

digital video output.

TMS320AV7110 bảng dữ liệu(PDF) 49 Page - Texas Instruments

TMS320AV7110 bảng dữ liệu(HTML) 49 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

bảng dữ liệu tải về

Link URL