SH7720 Datasheet, PDF (937/1524 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 26 LCD Controller (LCDC)
26.3.5 LCDC Start Address Register for Upper Display Data Fetch (LDSARU)
LDSARU sets the start address from which data is fetched by the LCDC for display of the LCDC
panel. When a DSTN panel is used, this register specifies the fetch start address for the upper side
of the panel.
Bit
Bit Name Initial Value R/W Description
31 to 28 
All 0
R
Reserved
These bits are always read as 0. The write value
should always be 0.
27, 26 
All 1
R
Reserved
These bits are always read as 1. The write value
should always be 1.
25 to 4 SAU25 to All 0
SAU4
R/W Start Address for Upper Display Data Fetch
The start address for data fetch of the display data
must be set within the synchronous DRAM area of
area 3.
3 to 0 
All 0
R
Reserved
These bits are always read as 0. The write value
should always be 0.
Notes: 1.
2.
The minimum alignment unit of LDSARU is 512 bytes when the hardware rotation
function is not used. Write 0 to the lower nine bits. When using the hardware rotation
function, set the LDSARU value so that the upper-left address of the image is aligned
with the 512-byte boundary.
When the hardware rotation function is used (ROT = 1), set the upper-left address of
the image, which can be calculated from the display image size in this register. The
equation below shows how to calculate the LDSARU value when the image size is 240
× 340 and LDLAOR = 256. The LDSARU value is obtained not from the panel size but
from the memory size of the image to be displayed. Note that LDLAOR must be a
binary exponential at least as large as the horizontal width of the image. Calculate
backwards using the LDSARU value (LDSARU − 256 (LDLAOR value) × (320 − 1)) to
ensure that the upper-left address of the image is aligned with the 512-byte boundary.
LDSARU = (upper-left address of image) + 256 (LDLAOR value) × 319 (line)
Rev. 3.00 Jan. 18, 2008 Page 875 of 1458
REJ09B0033-0300