ST7781
HWM: The ST7781 writes data in high speed with low power consumption by setting HWM = 1. The data to be written
within the window address area is buffered in order to write the data in units of horizontal lines. This can
minimize the Number of RAM access and the power consumption required in data write operation.
When HWM = 1, make sure to set AM = 0 (horizontal direction) and write the data in each horizontal line of the
window address area at a time. If the data is not enough to rewrite the horizontal line of the window address
area, the DRAM data in that line is not overwritten.
Notes1: The ST7781 requires no dummy write operation in high-speed write operation.
Note 2. When terminating DRAM data write operation in the middle of the line and executing another instruction, the
data in the buffer is cleared.
BGR: Reverses the order from RGB to BGR in writing 18-bit pixel data in the DRAM.
BGR = 0: Write data in the order of RGB to the DRAM.
BGR=0
D17 D16 D15 D14 D13 D12 D11 D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
R5 R4 R3 R2 R1 R0 G5 G4 G3 G2 G1 G0 B5 B4 B3 B2 B1 B0
BGR = 1: Reverse the order from RGB to BGR in writing data to the DRAM.
BGR=1
D17 D16 D15 D14 D13 D12 D11 D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
B5 B4 B3 B2 B1 B0 G5 G4 G3 G2 G1 G0 R5 R4 R3 R2 R1 R0
TRI: When TRI = “1”, data are transferred to the internal DRAM in 8-bit x 3 transfers mode via the 8-bit interface.It is
also possible to send data via the 16-bit interface in the transfer mode that realizes display in 262k colors in
combination with DFM bits. When not using these interface modes, be sure to set TRI = “0”.
DFM: Set the mode of transferring data to the internal RAM when TRI = “1”.
TRI
DFM
8080-16bits Interface Color Format
0
*
1
0
1
1
Ver. 1.7
47
SITRONIX [ SITRONIX TECHNOLOGY CO., LTD. ]
