PCA84C646P PHILIPS [NXP Semiconductors], PCA84C646P Datasheet - Page 19

• Manufacturer Part Number: PCA84C646P
• Description: Microcontrollers for TV tuning control and OSD applications
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
10 DISPLAY RAM ORGANIZATION
The display RAM is organized as 64
The general format of each RAM location is as follows:
Table 9 Format of Character Font Code
Table 10 Description of Character Font Code bits
Table 11 Selection of Background and Foreground colour
1995 Jun 15
C5 to C0
T3 to T1
T0
SYMBOL
– Customer designed Character Font Codes (62)
– Carriage Return Code (1)
– Space Code (1).
– Foreground colour and Blinking
– Character size and Line space
– Background colour and End-of-Display .
Microcontrollers for TV tuning
control and OSD applications
Bits <9-4> hold data, comprising:
Bits <3-0> contain the attributes of the Character Font:
C5
9
(RED)
If bits <9-4> are in the range (00H to 3DH), then this is a Character Font Code and 1 from 62 customer
designed character fonts can be selected.
Bits <3-1> determine the (Foreground) colour (1 out of 8) of this character; see Table 11.
Blinking of this character is controlled by bit <0>. See Section 12.3 for duty cycle and frequency control.
T3
0
0
0
0
1
1
1
1
When T0 = 0; blinking is OFF.
When T0 = 1; blinking is ON. Blinking rate:
C4
8
Character Font Code (00H - 3DH)
C3
7
10 bits.
C2
(GREEN)
6
T2
0
0
1
1
0
0
1
1
C1
5
DESCRIPTION
1
19
16
10.1
There are three data formats for the display RAM code
1. Character Font Code
2. Carriage Return Code
3. Space Code.
The three data formats and their descriptions are shown in
Tables 9 to 17. Figure 14 illustrates an example of the
timing of FB, R, G, and B pulses when displaying a line of
dots stream in a character.
FB = VOB; R = VOW0, G = VOW1; B = VOW2.
Figure 15 shows an example of the screen which includes
some Cariage Return and Space codes.
,
1
C0
32
4
, 1
64
Description of display RAM codes
(BLUE)
or
T1
1
0
1
0
1
0
1
0
1
128
T3
3
PCA84C646; PCA84C846
Foreground colour
f
VSYNC
.
T2
2
black
blue
green
cyan
red
magenta
yellow
white
Preliminary specification
T1
COLOUR
1
Blink
T0
0