S1D13700F01 Epson Electronics America, Inc., S1D13700F01 Datasheet - Page 63

• Manufacturer Part Number: S1D13700F01
• Description: Embedded Memory Graphics Lcd Controller
• Manufacturer: Epson Electronics America, Inc.

Epson Research and Development
Vancouver Design Center
OVLAY
bit 4
bit 3
bit 2
Hardware Functional Specification
Issue Date: 2005/12/13
REG[18h] Overlay Register
Address = 8018h
7
n/a
6
Default = 00h
Note
Note
The OVLAY command selects layered screen composition and screen text/graphics mode
when indirect addressing is used. The values from REG[18h] are passed as parameters
when the OVLAY command is issued. For further information on the OVLAY command,
see Section 11.1.7, “OVLAY” on page 74.
3 Layer Overlay Select (OV)
This bit determines how many layers are used when graphics mode is enabled. For mixed
text and graphics, this bit must be set to 0.
When this bit = 0, two layers are used.
When this bit = 1, three layers are used.
Screen Block 3 Display Mode (DM1)
This bit determines the display mode for screen block 3.
When this bit = 0, screen block 3 is configured for text mode.
When this bit = 1, screen block 3 is configured for graphics mode.
Screen Block 1 Display Mode (DM0)
This bit determines the display mode for screen block 1.
When this bit = 0, screen block 1 is configured for text mode.
When this bit = 1, screen block 1 is configured for graphics mode.
Screen blocks 2 and 4 can display graphics only.
Screen blocks 2 and 4 can display graphics only.
5
3 Layer Overlay
Select
4
Revision 4.05
Screen Block 3
Display Mode
3
Screen Block 1
Display Mode
2
Layer Composition Method bits 1-0
1
Read/Write
X42A-A-002-04
S1D13700F01
0
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