P83C266BDR datasheet(67/92 Pages) PHILIPS

67 / 92 page

1999 Mar 10

Philips Semiconductors

Product speciﬁcation

Microcontrollers for PAL/SECAM TV

with OSD and VST

P8xCx66 family

17.14 OSD vertical debouncing circuit

The HSYNC and VSYNC signals entering the OSD circuit are usually extracted from the horizontal and vertical deflection

units of a television set. The shaping and timing of these signals is therefore related to several external conditions that

all have certain tolerances. The trigger levels of the input circuitry also influence the internal timing of HSYNC and

VSYNC. In the odd field the leading edge of both signals is very close, so jitter on one or both of them may result in

occasionally miscounting the number of lines in a field causing a displayed character to bounce up and down on a line.

To avoid this situation the HSYNC signal is delayed by a number of dot clocks. Because the relationship between HSYNC

and VSYNC is not fully known there are 16 user selectable delays available. The period of the horizontal starting position

plus the HDEL delay cannot exceed the HSYNC period.

17.14.1 HORIZONTAL DELAY REGISTER (HDEL)

Table 76 Horizontal Delay Register (SFR address C6H)

Table 77 Description of HDEL bits

Table 78 Selection of HSYNC delay

76543210

−−−−

HDEL3

HDEL2

HDEL1

HDEL0

BIT

SYMBOL

DESCRIPTION

7to4

−

These 4 bits are reserved.

HDEL3

HSYNC delay. The state of these 4 bits determines the delay time applied to the

HSYNC signal, see Table 78.

HDEL2

HDEL1

HDEL0

HDEL3

HDEL2

HDEL1

HDEL0

NO. OF DOT

CLOCKS

DELAY TIME AT

5 MHz (

µs)

DELAY TIME AT

10 MHz (

µs)

00000

0001

6.4

3.2

0010

12.8

6.4

0011

19.2

9.6

0100

128

25.6

12.8

0101

160

0110

192

38.4

19.2

0111

224

44.8

22.4

1000

256

51.2

25.6

1001

288

57.6

28.8

1010

320

1011

352

70.4

35.2

1100

384

76.8

38.4

1101

416

83.2

41.6

1110

448

89.6

44.8

1111

480

P83C266BDR Datenblatt(PDF) 67 Page - NXP Semiconductors

P83C266BDR Datenblatt(HTML) 67 Page - NXP Semiconductors

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

Datenblatt Download

Link URL