Epson Research and Development
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Vancouver Design Center
Programming Notes and Examples
S1D13505
Issue Date: 01/02/05
X23A-G-003-07
Description: This function prepares the system for split screen operation. In order for split screen
to function the starting address in the display buffer for the upper portion (screen 1),
and the lower portion (screen 2) must be specified. Screen 1 is always displayed
above screen 2 on the display regardless of the location of their respective starting
addresses.
Parameters: DevID
- registered device ID
Scrn1Addr
- offset in display buffer, in bytes, to the start of screen 1
Scrn2Addr
- offset in display buffer, in bytes, to the start of screen 2
Return Value: ERR_OK
- operation completed with no problems
Note
It is assumed that the system has been properly initialized prior to calling seSplitInit().
int seSplitScreen(int DevID, int WhichScreen, long VisibleScanlines)
Description: Changes the relevant registers to adjust the split screen according to the number of
visible lines requested. WhichScreen determines which screen, screen 1 or screen 2,
to change.
The smallest screen 1 can be set to is one line. This is due to the way the register
values are used internally on the S1D13505. Setting the line compare register to zero
results in one line of screen 1 being displayed followed by screen 2.
Parameters: DevID
- registered device ID
WhichScreen- must be set to 1 or 2, or use the constants SCREEN1 or SCREEN2,
to identify which screen to base calculations on
VisibleScanlines- number of lines to show for the selected screen
Return Value: ERR_OK
- operation completed with no problems
ERR_HAL_BAD_ARG- argument VisibleScanlines is negative or is greater than
vertical panel size or WhichScreen is not SCREEN1 or SCREEN 2.
Note
seSplitInit() must be called before calling seSplitScreen()
Changing the number of lines for one screen will also change the number of lines in the
other screen (e.g. increasing screen 1 lines by 5 will reduce screen 2 lines by 5).
int seVirtInit(int DevID, DWORD VirtX, DWORD * VirtY)
Description: This function prepares the system for virtual screen operation. The programmer
passes the desired virtual width, in pixels, as VirtX. When the routine returns, VirtY
will contain the maximum number of lines that can be displayed at the requested
virtual width.
Parameter:
DevID
- registered device ID
VirtX
- horizontal size of virtual display in pixels.
(Must be greater or equal to physical size of display)
VirtY
- a return placeholder for the maximum number of lines available
given VirtX