
5 REGISTERS
C-1-16
EPSON
SID13705 HARDWARE FUNCTIONAL
SPECIFICATION
bits 7-0
Memory Address Offset Bits [7:0] (Landscape Modes Only)
This register is used to create a virtual image by setting a word offset between the last
address of one line and the first address of the following line. If this register is not equal
to zero, then a virtual image is formed. The displayed image is a window into the larger
virtual image. See Figure 5-1, “Screen-Register Relationship,” on page C-1-17.
This register has no effect in portrait modes. See “ REG[1Ch] Line Byte Count Register
for Portrait Mode” on page C-1-20.
REG[13h] bits 1-0
Screen 1 Vertical Size Bits [9:0]
REG[12h] bits 7-0
These bits determine the height (in lines) of Screen 1.
In landscape modes, if this register is programmed with a value, n, where n is less than
the Vertical Panel Size (REG[06h], REG[05h]), then lines 0 to n of the panel contain
Screen 1 and lines n+1 to REG[06h], REG[05h] of the panel contain Screen 2. See Fig-
ure 5-1, “Screen-Register Relationship,” on page C-1-17.
In portrait modes this register must be programmed greater than, or equal to the Vertical
Panel Size, REG[06h] and REG[05h]. See “9 PORTRAIT MODE” on page C-1-29.
REG[11h] Memory Address Offset Register
Address = 0x039FFF1
Read/Write
Memory
Address Offset
Bit 7
Memory
Address Off-
set Bit 6
Memory
Address Off-
set Bit 5
Memory
Address Off-
set Bit 4
Memory
Address Off-
set Bit 3
Memory
Address Off-
set Bit 2
Memory
Address Off-
set Bit 1
Memory
Address Off-
set Bit 0
REG[12h] Screen 1 Vertical Size Register (LSB)
Address = 0x039FFF2
Read/Write
Screen 1 Verti-
cal Size Bit 7
Screen 1 Verti-
cal Size Bit 6
Screen 1 Verti-
cal Size Bit 5
Screen 1 Verti-
cal Size Bit 4
Screen 1 Verti-
cal Size Bit 3
Screen 1 Verti-
cal Size Bit 2
Screen 1 Verti-
cal Size Bit 1
Screen 1 Verti-
cal Size Bit 0
REG[13h] Screen 1 Vertical Size Register (MSB)
Address = 0x039FFF3
Read/Write
n/a
Screen 1 Verti-
cal Size Bit 9
Screen 1 Verti-
cal Size Bit 8