STV9432TA

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8 - BEAM CURRENTS MEASUREMENT

8.1 - BEAM CURRENT MEASUREMENT REGISTERS

mand (see TIMG register).

RCI Register: Red Beam Current Input

GCI Register: Green Beam Current Input

BCI Register: Blue Beam Current Input

8.2 - BEAM CURRENT MEASUREMENT TRIGGER

The Beam Currents Measurement is performed according to the setting of SBN and TIMG registers :

8.2.1 - SBN Register

This 8 bits register holds the "sampling bloc" number.

The sampling bloc is a set of 4 consecutive scan lines, the first of which is used for sampling the video

timings or Beam currents. The reset value of this register is 0.

8.2.2 - TIMG Register

This 8 bits register holds the following parameters:

To initiate a Beam Currents Measurement cycle:

- program the Sampling Bloc Number in the SBN

Register,

- program the TIMG Register, with:

"SELECT" bit = 0, "ADCDLY" bits specify the

sampling time during HFly, "STM" bit = 1 (Start

Measurement).

As soon as the measurement cycle is finished, the

"STM" bit is automatically reset by the device. Af-

ter a Beam Currents Measurement cycle, reading

a zero in STM bit of TIMG register means that the

measurement is completed and the MCU may

read the results in RCI, GCI, and BCI registers.

The reset value of this register is 0.

4012

RCI7

RCI6

RCI5

RCI4

RCI3

RCI2

RCI1

RCI0

4013

GCI7

GCI6

GCI5

GCI4

GCI3

GCI2

GCI1

GCI0

4014

BCI7

BCI6

BCI5

BCI4

BCI3

BCI2

BCI1

BCI0

4015

SBN7

SBN6

SBN5

SBN4

SBN3

SBN2

SBN1

SBN0

4016

STM

NFR1

NFR0

ADCDLY3

ADCDLY2

ADCDLY1

0

SELECT

STM

: Start Measurement Bit. This bit

start

the

measurement

sequence, depending on the

measurement

selection

bit.

When

measurement is com-

pleted the IC will reset this bit to

0.

NFR [1:0]

: NFR number of measurement

frames, 1 to 4 frames

ADCDLY

[3:1]

: Cut-off Beam current ADC sam-

SELECT

: Selection of Beam current mea-

surement (0) or Timing mea-

surement (1)

4