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Epson Research and Development

 

Vancouver Design Center

 

 

12.1.1 How to Set Up Default SwivelView Mode

The following describes the register settings needed to set up Default SwivelView Mode for a 240x320x8 bpp image:

Select Default SwivelView Mode: REG[1Bh] bit 7 = 1 and bit 6 = 0

The display refresh circuitry starts at pixel “B”, therefore the Screen 1 Start Address register must be programmed with the address of pixel “B”, i.e.

REG[10h], REG[0Dh], REG[0Ch] =

AddressOfPixelB

 

 

 

= (AddressOfPixelA + ByteOffset)

 

 

=

240pixels

8bpp

– 1

AddressOfPixelA +

--------------------------------------------8bpb

 

 

 

 

= AddressOfPixelA + EFh

Where bpp is bits-per-pixel and bpb is bits-per-byte.

The Line Byte Count Register for SwivelView Mode must be set to the virtual-image width in bytes, i.e.

REG[1Ch] =

-----------------------------------------256

= 256-------- = 256 = 00h :see REG[1Ch] for explanation

 

(8bpb ) ⎟ (8bpp)

1

Where bpb is bits-per-byte and bpp is bits-per-pixel.

Panning is achieved by changing the Screen 1 Start Address register:

Increment the register by 1 to pan horizontally by one byte, e.g. one pixel in 8 bpp mode

Increment the register by twice the effective value of the Line Byte Count register to pan vertically by two lines, e.g. add 200h to pan by two lines in the example above.

Note

Vertical panning by a single line is not supported in Default SwivelView Mode.

S1D13705

Hardware Functional Specification

X27A-A-001-10

Issue Date: 02/02/01

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Image 84
Epson S1D13705 technical manual How to Set Up Default SwivelView Mode, Where bpp is bits-per-pixel and bpb is bits-per-byte