October 1994

22

Philips Semiconductors

Product specification

8-bit microcontrollers with OSD and VST

84C44X; 84C64X; 84C84X

12.6.1

Table 11 Derivative register OSDCA (address 40H)

Table 12 Description of OSCDA bits

7

6

5

4

3

2

1

0

CC34

CC24

CC14

RBLK

ROUND

STBY

VLVL

HLVL

BIT SYMBOL

FUNCTION

7

CC34

Character colour code bits.

These bits are used for colour selection purposes. See Table 24.

6

CC24

5

CC14

4

RBLK

Raster blanking control (see Fig.24). When the RBLK bit is:

Logic 1, the VOB output is driven HIGH to display the OSD characters on a blank screen.

Logic 0, the VOB output returns to its normal output state on the trailing edge of VSYNCN.

3

ROUND

Character rounding control (see Figs 22 and 23). The rounding function generates half dots where

the corners of two dots meet. The rounding function also works with multiple cell characters.

When the ROUND bit is:

Logic 1, the rounding function is enabled.

Logic 0, the rounding function is disabled.

2

STBY

Stand-by. This bit is used to enable or disable the OSD facility. When the STBY bit is:

Logic 1, the OSD oscillator is disabled.

Logic 0, the OSD oscillator is enabled and the OSD facility is available.

1

VLVL

Vertical synchronous signal level (see Fig.21).

This bit selects the active level of the VSYNCN input signal. When the VLVL bit is:

Logic 1, VSYNCN is active HIGH.

Logic 0, VSYNCN is active LOW.

0

HLVL

Horizontal synchronous signal level (see Fig.21).

This bit selects the active level of the HSYNCN input signal. When the HLVL bit is:

Logic 1, HSYNCN is active HIGH.

Logic 0, HSYNCN is active LOW.

Fig.21 VSYNCN and HSYNCN active level.

handbook, full pagewidth

(VSYNCN)

HSYNCN

(HLVL = VLVL = 0)

(HLVL = VLVL = 1)

characters can be displayed

(VSYNCN)

HSYNCN

MCD180