HD66787 Datasheet, PDF (46/159 Pages) Renesas Technology Corp – 528-channel, One-chip Driver with 262,144-color Display RAM and Power Supply Circuit for Low-temperature Poli-Si TFT (LTPS-TFT) Panels with Incorporat

HD66787
Preliminary
When RGB-I/F is selected, RAM data are changeable through the system interface. This write operation
must be performed while display data are not being transmitted through the RGB-I/F (ENABLE = High).
When reverting from the system interface mode to the data transmission through the RGB interface, make a
new setting for the address set and index (R22h) after changing the aforementioned settings.
VSYNC interface mode
The internal display operation is synchronized with the frame-synchronizing signal (VSYNC) in the
VSYNC interface mode. By writing data to RAM at a fixed speed on the falling edge of VSYNC, it
enables moving pictures display with a system interface. In this case, there are some constraints in the
RAM write speed and methods. For details, see the “External Display Interface” section.
In the VSYNC-I/F mode, only VSYNC input is valid. Other input signals for the external display interface
are invalid.
The front porch (FP), back porch (BP) periods and display period (NL) are automatically generated in
accordance to the frame synchronizing signal (VSYNC) according to the register setting of HD66787.
Rev.0.22, May.23.2003, page 46 of 159