hd66789 Renesas Electronics Corporation., hd66789 Datasheet - Page 92

• Manufacturer Part Number: hd66789
• Description: 528-channel, One-chip Driver For Amorphous Tft Panels With 262,144-color Display Ram, Power Supply Circuit, And Gate Circuit
• Manufacturer: Renesas Electronics Corporation.

HD66789
6-bit RGB interface
The 6-bit RGB interface is selected by setting RIM1-0 bits to 10. The display operation is synchronized
with VSYNC, HSYNC, and DOTCLK signals. Display data are transmitted to RAM in synchronization
with the display operation through 6-bit RGB data bus (PD17-12) according to data valid signal (VLD),
and the data enable signal (ENABLE). Unused pins (PD11 to 0) must be fixed to either IOVcc or GND
level.
The instructions are set only through a system interface.
Data transmission synchronization in 6-bit RGB interface mode
The HD66789 incorporates a transmission counter to count the first, second, third data transmissions in the
6-bit RBG interface mode. The transmission counter is reset to the first transmission on the falling edge of
VSYNC. When a discrepancy occurs in the transmission of first, second and third data, the counter is reset
so that a first data transmission will be made at the start of each frame (on the falling edge of VSYNC) and
the data transmission restarts in the correct order from the next frame. In case of displaying moving
pictures, which requires consecutive data transfer, this function minimizes the effect from the discrepancy
in the data transmission and makes it easy to return to the normal display.
The internal display operation is executed by pixel. Note that each DOTCLK input must correspond to a
pixel. Otherwise data transmission discrepancies will occur and affect the displays of the current and
ensuing frames.
Rev.0.12, May 09 2003, page 92 of 156
Write Data
to GRAM
INPUT
RAM data write
R5
PD
17
R4
PD
16
1
st
Transmission
R3 R2
PD
15
LCDC
PD
14
Data format for 6-bit interface
R1
PD
13
R0
PD
6-bit RGB interface
12
G5
PD PD PD PD PD PD PD PD PD PD PD PD
17
G4
16
2
nd
One Pixel
6
Transmission
G3
15
GND
G2
14
12
ENABLE
PD17-12
PD11-0
VSYNC
HSYNC
DOTCLK
VLD
G1
13
262,144 colors are available in 6-bit system interface.
G0
12
HD66789
B5
17
B4
16
3
rd
Transmission
B3
15
B2
14
B1
13
B0
12
Preliminary