Epson Research and Development

Page 45

Vancouver Design Center

 

 

 

int seVirtInit(int device, int xVirt, long *yVirt)

Description: Creates a virtual display with the given horizontal size and determines the maximum number of available lines.

Parameter: device - registered device ID

xVirt - horizontal size of virtual display in pixels. Must be greater or equal to physical size of display.

yVirt - seVirtInit() calculates the maximum number of lines available for virtual display and returns value in yVirt.

Return Value: ERR_OK - operation completed with no problems ERR_INVALID_REG_DEVICE - device argument is not valid. ERR_HAL_BAD_ARG - argument xVirt is too large. Select xVirt such that the Memory Address Offset register does not exceed 0x3ff. The maximum allowable xVirt is 0x3ff * (16 / bpp). If bpp is 15, use the above equation with bpp = 16.

Note

seSetInit() must have been called before calling seVirtInit(). This is because the VNDP is used for timing, and this would not be possible if the registers were not first initialized.

int seVirtMove(int device, BYTE WhichScreen, int x, int y)

Description: Pans or scrolls the virtual display.

Parameter: device - registered device ID

WhichScreen - Use one of the following definitions: SCREEN1 or SCREEN2. SCREEN1 is the top screen.

x - new starting X position in pixels y - new starting Y position in pixels

Return Value: ERR_OK - operation completed with no problems ERR_INVALID_REG_DEVICE - device argument is not valid. ERR_HAL_BAD_ARG - argument WhichScreen is not SCREEN1 or SCREEN2.

-argument Y is too large.

-bpp is invalid in HAL structure (this would occur if the application changed the registers directly instead of calling seSetBitsPerPixel()).

Note

seVirtInit() must have been called once before calling seVirtMove().

Programming Notes and Examples

S1D13504

Issue Date: 01/02/01

X19A-G-002-07

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Epson S1D13504 Int seVirtInitint device, int xVirt, long *yVirt, Int seVirtMoveint device, Byte WhichScreen, int x, int y