s Example of System Configuration
AVDP6 is a display control device that operates as 16 bit or 32 bit I/O device on the external general purpose bus
of CPU on the system in which the device is built-in. Because CPU I/F of AVDP6 uses asynchronous I/F, it can be
controlled with general purpose SRAM I/F. SDRAM is connected on the local bus of AVDP6 to be used as video
memory. The timing for this SDRAM is made by AVDP6 independently. In the SDRAM, bit map image and palette
data that are displayed by AVDP6 are stored, and in addition, memory domain of SDRAM can be mapped directly
on the bus of CPU so that the vacant space is utilized as the work domain of CPU. The memory space of SDRAM is
controlled with general purpose SDRAM I/F.
Examples of system configuration are shown below by application.
Independent (free running) system
When displaying bit map image stored in the video memory independently, it is possible to output sync
signal and display data that are compatible with various scan timing functions by supplying dot clock that is
suited to the display device and by writing timing parameter into the registers for internal scan timing. Since
the display data are outputted as analog and digital data, an LCD panel can be connected directly to the device
and video signal can be created by Video Encoder device.
OSD of NTSC digital images
This is an example of system configuration that uses AVDP6 to display OSD images of digital video
equipment conforming to NTSC (SDTV) such as DVD. Since AVDP6 is equipped with input / output pins for
digital images, the digital video signal can be inputted without converting it to analog signal, processed with
OSD and α blending without deteriorating the quality of images, and then outputted. When displaying bitmap
image of AVDP6 for external video with OSD, it is necessary to synchronize the external video signal with
scanning of AVDP6. At this time, OSD image can be synchronized with external video by inputting sync
signal of the external video into scan control circuit of AVDP6. (As the dot clock, use the clock that is
synchronized with external video signal.)
The digital image I/F of AVDP6 is compatible with digital I/F that conforms to CCIR-Rec601/656 (ITU656).