NEC µPD72257 Preliminary User's Manual page 207

Video Output
Bit Bit name
8 BGR
5 bit 5
3 to 1 LCDBPP[2:0]
0 LCDEN
Function
Blue-Red swapped output
By setting BGR the display output signals of the blue VOnB[5:0] adn red VOnR[5:0]
channels are swapped.
0 RGB output
1 BGR output (VOnB[5:0] and VOnR[5:0] swapped)
The default value "0" of this bit must be changed to "1" after reset and must not be altered
afterwards.
Colour format selection
011
8 bpp CLUT(8) mode
B
101
18 bpp RGB(666) true colour mode
B
110
16 bpp RGB(565) true colour mode
B
The colour format selection determines the colour format of the pixel data in the
framebuffer as well as the format of the display data output.
Video Output control enable
LCDEN = 1 enables the Video Output control signals VOnHSYNC, VOnVSYNC, VOnCLK,
VOnEN.
0 control and display data signals disabled (output low level)
1 control signals enabled (active)
LCDEN = 0 disables also the display data signals VOnR[5:0], VOnG[5:0], VOnB[5:0].
Note that LCDEN = 1 only enables the control, but not the data signals. Those have to
be additionally enabled by LCDPWR = 1.
Preliminary User's Manual S19203EE1V3UM00
Chapter 7
207