Programming Model
4.1.20 Vertical Border End Register (VBER): Address 95H	.
This 13 bit register defines the time, in units of a raster, from the start of the VSYNC pulse to the end of the border display. (i.e. the first raster on which the border is not present).
If N rasters are required in this time, then value (N-1) should be programmed into the VBER
If no border is required, then this register must be programmed to the same value as the VDER
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VEER value
4.1.21 Vertical Cursor Start Register (VCSR): Address 96H
i
This is a 15 bit register. The lower 13 bits define the time, in units of a raster, from the start of the VSYNC pulse to the start of the cursor display. If N rasters are required in this time, then value (N-1) should be programmed into the VCSA. The upper 2 bits are used to control the display of the cursor in duplex LCD mode. They should be programmed to zero in all other modes.
When the upper 2 bits are programmed to bell (split screen) the meaning of VCSR and VCER are altered as follows. The cursor is displayed in the lower half-screen only from the value of VDSR to the value of VCSR, and again in the upper half screen only from the value of VCER to the value of VDER. This allows a cursor to be positioned across the boundary of the upper and lower half screens of an LCD.
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1 0 0 1 0 7 7 0	x x x x x x x x x x x x x x xl
VCSR value
- 00	normatopenauon
01	upper halt-screen only
10	lower hall-screen only
11	split screen
4.1.22 Vertical Cursor End Register (VCER): Address 97H
This 13 bit register defines the time, in units of a raster, from the start of the V SYNC pulse to the end of the cursor display. (i.e. the first raster on which the cursor is not present).
If N rasters are required in this time, then value (N-1) should be programmed into the VCER.
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VCER value
23