Philips S1D13505 用户手册
Epson Research and Development
Page 35
Vancouver Design Center
Programming Notes and Examples
S1D13505
Issue Date: 01/02/05
X23A-G-003-07
5.3 Split Screen
Occasionally the need arises to display two distinct images on the display. For example, we
may write a game where the main play area will rapidly update and we want a status display
at the bottom of the screen.
may write a game where the main play area will rapidly update and we want a status display
at the bottom of the screen.
The Split Screen feature of the S1D13505 allows a programmer to setup a display for such
an application. The figure below illustrates setting a 320x240 panel to have Image 1
displaying from scan line 0 to scan line 99 and image 2 displaying from scan line 100 to
scan line 239. Although this example picks specific values, image 1 and image 2 can be
shown as varying portions of the screen
an application. The figure below illustrates setting a 320x240 panel to have Image 1
displaying from scan line 0 to scan line 99 and image 2 displaying from scan line 100 to
scan line 239. Although this example picks specific values, image 1 and image 2 can be
shown as varying portions of the screen
.
Figure 5-5: 320x240 Single Panel For Split Screen
5.3.1 Registers
The other registers required for split screen operations, [10h] through [12h] (Screen 1
Display Start Address) and [18h] (Pixel Panning Register), are described in Section 5.2.1
on page 32.
Display Start Address) and [18h] (Pixel Panning Register), are described in Section 5.2.1
on page 32.
Figure 5-6: Screen 1 Line Compare
Scan Line 0
Image 1
...
Scan Line 99
Scan Line 100
Image 2
...
Scan Line 239
Screen 1 Display Line Count Register = 99 lines
REG[0E] Screen 1 Line Compare Register 0
Line
Compare Bit
7
Compare Bit
7
Line
Compare Bit
6
Compare Bit
6
Line
Compare Bit
5
Compare Bit
5
Line
Compare Bit
4
Compare Bit
4
Line
Compare Bit
3
Compare Bit
3
Line
Compare Bit
2
Compare Bit
2
Line
Compare Bit
1
Compare Bit
1
Line
Compare Bit
0
Compare Bit
0
REG[0F] Screen 1 Line Compare Register 1
n/a
n/a
n/a
n/a
n/a
n/a
Line
Compare Bit
9
Compare Bit
9
Line
Compare Bit
8
Compare Bit
8