83C055 Philips Semiconductors, 83C055 Datasheet - Page 24

• Manufacturer Part Number: 83C055
• Description: Microcontrollers for TV and video MTV
• Manufacturer: Philips Semiconductors

Philips Semiconductors
Table 28 Shadowing modes determined by bits SHM2 to SHM0 (register OSMOD) and Sh (register OSAT)
Note
1. The mode names are based on the position of an apparent light source, ranging from the lower left (South-west)
13.9
Table 29 OSD Control Register OSORG (address C2H)
Table 30 Description of OSORG bits (note 1)
Notes
1. Neither the Hstart nor Vstart parameter is affected by the D line attribute that is used to display double-sized
2. Counting variations in Wc, there may be 17 to 143 VCLK clock cycles from the end of HSYNC to the start of the first
3. Subsequent character rows occur directly below the first, such that the last scan line of one row is directly followed
1996 Mar 22
Microcontrollers for TV and video (MTV)
clockwise to the lower right (South-east); see Fig.8.
characters.
character of each row.
by the first scan line of the next row. Successive New Line characters (with or without the Short Row designation)
can be used to vertically separate text rows on the screen.
7 to 3
2 to 0
HS4
BIT
SHM2
7
OSD Control Register OSORG
X
0
0
0
0
1
1
1
1
HS4 to HS0 HStart field; defines the horizontal start position of all the on-screen character rows, as
VS2 to VS0
SYMBOL
HS3
6
SHM1
X
0
0
1
1
0
0
1
1
approximately a multiple of 4 VCLK clock cycles. Active display begins after the trailing
edge of HSYNC at the position:
Where (HStart) is the decimal value of bits (HS4 to HS0); note 2.
VStart field; defines the vertical start position of the first on-screen character row, as
approximately a multiple of 4 HSYNC pulses. Active display begins after the field’s time
reference point (a range of 3 to 31)at the position:
Where (VStart) is the decimal value of bits (VS2 to VS0); note 3.
HP
VP
HS2
=
=
5
4
4
SHM0
X
0
1
0
1
0
1
0
1
VStart
HStart
HS1
4
–
+
1
1
Sh
24
HSYNC pulses
1
1
1
1
1
1
1
1
0
VCLK clock cycle
HS0
3
DESCRIPTION
South-west
West
North-west
North
North-east
East
South-east
Full surround
No Shadowing
+
VS2
SHADOWING MODE
one single-sized character width
2
83C145; 83C845
83C055; 87C055
VS1
1
Product specification
(1)
VS0
0