VDP313XY Ver la hoja de datos (PDF) - Micronas

Número de pieza

componentes Descripción

Fabricante

VDP313XY

Video Processor Family

Micronas 

VDP 313xY

ADVANCE INFORMATION

In each field two sets of measurements can be taken:

a) The picture tube measurement returns results for

– cutoff R

– cutoff G

– cutoff B

– whitedrive R or G or B (sequentially)

b) The picture measurement returns data on

– active picture maximum current

– active picture minimum current

The tube measurement is automatically started when

the cutoff blue result register is read. Cutoff control for

RGB requires one field only while a complete whit-

edrive control requires three fields. If the measurement

mode is set to ‘offset check’, a measurement cycle is

run with the cutoff/whitedrive signals set to zero. This

allows to compensate the MADC offset as well as the

input the leakage currents. During cutoff and whit-

edrive measurements, the average beam current lim-

iter function (see Section 2.11.3. on page 23) is

switched off and a programmable value is used for the

brightness setting. The start line of the tube measure-

ment can be programmed via I2C-bus, the first line

used for the measurement, i.e. measurement of cutoff

red, is 2 lines after the programmed start line.

The picture measurement must be enabled by the con-

trol microprocessor after reading the min./max. result

registers. If a ‘1’ is written into bit 2 in subaddress 25,

the measurement runs for one field. For the next mea-

surement a ‘1’ has to be written again. The measure-

ment is always started at the beginning of active video.

The vertical timing for the picture measurement is pro-

grammable, and may even be a single line. Also the

signal bandwidth is switchable for the picture measure-

ment.

Two horizontal windows are available for the picture

measurement. The large window is active for the entire

active line. Tube measurement is always carried out

with the small window. Measurement windows for pic-

ture and tube measurement are shown in Fig. 2–19.

2.11.2.SCART Output Signal

The RGB output of the VDP 313xY can also be used

to drive a SCART output. In the case of the SCART

signal, the parameter CLMPR (clamping reference)

has to be set to 1. Then, during blanking, the RGB out-

puts are automatically set to 50 % of the maximum

brightness. The DC offset values can be adjusted with

the cutoff parameters CR, CG, and CB. The amplitudes

can be adjusted with the drive parameters WDR,

WDG, and WDB.

active video

field 1/ 2

tube measurement

picture meas. start

picture meas. end

small window for tube

measurement (cutoff, whitedrive)

large window for active picture

picture meas. start

Fig. 2–19: Windows for tube and picture measure-

ments

22

Micronas

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