SH7205 Datasheet, PDF (1458/1904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7200 Series

Section 26 2D Graphics Engine (2DG)
Blit (Without blending)
DMAC3
Input image
04FFF40
004F400
004F400
Number of pixels = Nb
α value = αb
SB
buffer
DMAC2
AA AAA
A AA
A AA
The DMAC controlled by the CPU issues
the addresses of the both memories and
performs a memory-to-memory transfer.
DC
buffer
Number of pixels = Nb
Color value = result of operation
α value = replacement value = A
Image plane in the SDRAM
Plane 1 (α value only)
04FFF40
004F400
004F400
Plane 2 (αRGB)
AA AAA
A AA
A AA
Sets the number of pixels (Nc) to be transferred to the DC buffer. (By setting the GR_DCSET register)
Sets the number of pixels (Nb) to be transferred to the SB buffer. (By setting the GR_SABSET register)
Sets blitter operating mode. (By setting the BTYPE bits of the GR_BLTMODE register)
Selects the SB output data. (By setting the SBSEL bits of the GR_BLTMODE register)
Sets the SB image format. (By setting the SB_FMT bits of the GR_PIXLFMT register)
GALFA = (The value set by user), FBFA = 1
Procedure
Input α
↓
Input pixel (α color expansion)
= αb & (settings of the GR_BRDCOL
(RGB = red in the example))
↓
Weighted multiplication
(weighing each component of RGB by α value)
= αb & (αb × R, αb × G, αb × B)
↓
For example, when the GALFA bit is set to 1,
replacemen of α value = αb → A
Executes the processing. (By setting the GR_BLTPLY register to 10)
Output = A & (αbR (R data), αbG (G data),
αbB (B data))
Data output to the DC buffer
2DG
Figure 26.31 Example of Color Gradation Processing (1)
Rev. 1.00 Mar. 25, 2008 Page 1426 of 1868
REJ09B0372-0100