sed1355 ETC-unknow, sed1355 Datasheet - Page 192

• Manufacturer Part Number: sed1355
• Description: Sed1355 Embedded Ramdac Lcd/crt Controller
• Manufacturer: ETC-unknow

Page 36
7.3 Limitations
7.3.1 Updating Hardware Cursor Addresses
7.3.2 Reg[29h] And Reg[2Bh]
7.3.3 Reg [30h]
7.3.4 No Top/Left Clipping on Hardware Cursor
7.4 Examples
SED1355
X23A-G-003-05
There are limitations for using the hardware cursor/ink layer which should be noted.
All hardware cursor addresses must be set during VNDP (vertical non-display period). Check the
VNDP status bit (REG[0Ah] bit 7) to determine if you are in VNDP, then update the cursor address
register.
Bit seven of registers [29h] and [2Bh] are write only, and must always be set to zero as setting these
bits to one, will cause undefined cursor behavior.
Bit 7 of register [30h] is write only, therefore programs cannot determine the current cursor/ink layer
start address by reading register [30h]. It is suggested that values written to this register be stored
elsewhere and used when the current state of this register is required.
The SED1355 does not clip the hardware cursor on the top or left edges of the display. For cursor
shapes where the hot spot is not the upper left corner of the image (the hourglass for instance), the
cursor image will have to be modified to clip the cursor shape.
See Section 12, “Sample Code” for hardware cursor programming examples.
Epson Research and Development
Programming Notes and Examples
Vancouver Design Center
Issue Date: 99/04/27