Renesas R61509V - Manual (Page 96)

R61509V Target Spec
Rev. 0.11 April 25, 2008, page 96 of 181
Interface and Data Format
The R61509V supports system interface for making instruction and other settings, and external display
interface for displaying a moving picture. The R61509V can select the optimum interface for the display
(moving or still picture) in order to transfer data efficiently.
As external display interface, the R61509V supports RGB interface and VSYNC interface, which enables
data rewrite operation without flickering the moving picture on display.
In RGB interface operation, the display operation is executed in synchronization with synchronous signals
VSYNCX, HSYNCX, and DOTCLK. In synchronization with these signals, the R61509V writes display
data according to data enable signal (ENABLE) via RGB data signal bus (DB17-0). The display data is
stored in the R61509V’s GRAM so that data is transferred only when rewriting the frames of moving
picture and the data transfer required for moving picture display can be minimized. The window address
function specifies the RAM area to write data for moving picture display, which enables displaying a
moving picture and RAM data in other than the moving picture area simultaneously. To access the
R61509V’s internal RAM in high speed with low power consumption, use high-speed write function
(HWM = 1) in RGB or VSYNC interface operation.
In VSYNC interface operation, the internal display operation is synchronized with the frame
synchronization signal (VSYNCX). The VSYNC interface enables a moving picture display via system
interface by writing the data to the GRAM at faster than the minimum calculated speed in synchronization
with the falling edge of VSYNCX. In this case, there are restrictions in setting the frequency and the
method to write data to the internal RAM.
The R61509V operates in either one of the following four modes according to the state of the display. The
operation mode is set in the external display interface control register (R0Ch). When switching from one
mode to another, make sure to follow the relevant sequence in setting instruction bits.
Table 56 Operation Modes
Operation Mode RAM Access Setting (RM) Display Operation Mode (DM)
Internal clock operation
(displaying still pictures) System interface
(RM = 0) Internal clock operation
(DM1-0 = 00)
RGB interface (1)
(displaying moving pictures) RGB interface
(RM = 1) RGB interface
(DM1-0 = 01)
RGB interface (2)
(rewriting still pictures while
displaying moving pictures) System interface
(RM = 0) RGB interface
(DM1-0 = 01)
VSYNC interface
(displaying moving pictures) System interface
(RM = 0) VSYNC interface
(DM1-0 = 10)
Notes: 1. Instructions are set only via system interface.
2. When RGB interface is used, instructions should be transferred via clock synchronous serial
interface.
3. RGB and VSYNC interfaces cannot be used simultaneously.
4. Do not make changes to the RGB interface operation setting (RIM1-0) while RGB interface is
in operation.
5. See the “External Display Interface” section for the sequences when switching from one mode
to another.