S1D13705 Epson Electronics America, Inc., S1D13705 Datasheet - Page 103

• Manufacturer Part Number: S1D13705
• Description: S1d13705 Embedded Memory Lcd Controller
• Manufacturer: Epson Electronics America, Inc.

Epson Research and Development
Vancouver Design Center
Programming Notes and Examples
Issue Date: 01/02/13
Note
This routine first performs a formula rearrangement so that HNDP or VNDP can be solved.
Start with VNDP set to a small value. Loop increasing VNDP and solving the equation for
HNDP until satisfactory HNDP and VNDP values are found. If no satisfactory values are
found then divide CLKI and repeat the process. If a satisfactory frame rate still can’t be
reached - return an error.
Most passive (STN) panels are tolerant of nearly any combination of HNDP and VNDP
values, however panel specifications generally specify only a few lines of vertical non-
display period. The S1D13705 is capable of generating a vertical non-display period of
up to sixty-three lines. This amount of VNDP is far too great a non-display period and
will likely degrade display quality. Similarly, setting a large HNDP value may cause a
degrade in image quality.
If possible the system should be designed such that VNDP values of 7 or less lines and
HNDP values of 20 or less characters can be selected.
X27A-G-002-02
S1D13705
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