ST92196A STMicroelectronics, ST92196A Datasheet - Page 142

• Manufacturer Part Number: ST92196A
• Description: 8/16-bit Mcu For Tv Applications With Up To 96k Rom, On-screen-display And 1 Or 2 Data Slicers
• Manufacturer: STMicroelectronics

OSD CONTROLLER (Cont’d)
8.5.8.2 Horizontal Shift and Row Character Count
Address in Segment 22h: 2p + 2 (Bits 15:8), 2p + 3 (Bits 7:0). See
For each row to be displayed, the number of char-
acters in the row, and the horizontal position of the
row on the screen need to be specified.
Let’s assume that the start address of the current
row buffer is 2p (even address).
Bits 15:10 = RCN[5:0] Row Character Count
These bits define the number of characters to dis-
play in the current row.
The Display controller allows to display from 1 to
63 characters (in parallel mode) or 61 (in serial
mode, as the first 2 bytes are taken as attributes)..
For example, a 36 character row requires pro-
gramming RCN[5:0] = 24h.
Bits 9:0 = HS[9:0] Horizontal Shift
These bits define the horizontal shift value. They
specify, in terms of number of Pixel clock periods,
RCN5 RCN4
15
RCN3
RCN2 RCN1 RCN0
HS9
HS8
8
- ON SCREEN DISPLAY CONTROLLER (OSD)
HS7
7
the horizontal shift applied from the leading edge
of the Hsync pulse to the beginning of the first dis-
played character (1
3
Loading any value smaller than 01h is forbidden.
The result is given by the formula:
Horizontal shift = [HS[9:0]+ 47] * (2*PIXCLK)
(where PIXCLK is the clock issued from the Skew
Corrector). Refer to the Timing and Clock Control
chapter for programming information.
Figure 65. Row Position
rd
HS6
character in serial mode). Refer to
Horizontal
Shift
HS5
Figure
ST92x196
HS4
Displayed Row
59.
st
Event Line (Vertical Shift)
character in parallel modes,
HS3
HS2
HS1
Figure
HS0
0
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65.