4 Digit Hexadecimal Colors on Screen?

Other Hardware Displays
1

Hello. I have recently got a Seeed Studio TFT Screen (V2) for my Arduino. It includes some built in color codes, which by looking in their TFT library, I have found that they are 4 digit hexadecimal color codes. I know how to write colors in 6 digit hexadecimal (like in CSS), but how do these colors work, and how can I create my own colors (for example, orange) without having to cycle through all of the possible numbers?

These are the colors that are defined:

Red 0xf800
Green 0x07e0
Blue 0x001f
Black 0x0000
Yellow 0xffe0
White 0xffff

Thanks!

2

I have just figured it out.. It seems simpler than I thought!
It seems to be something like this:
0xRGBB, where R is red, G is green, and B is blue. Not entirely sure why there are two blue digits though!

3

In binary, the colors are RRRRGGGGGGBBBB which is a 16 bit val.. or 4 hex digits

5 red 6 green 5 blue binary bits
to convert from 24 bit color (like painbrush uses):

decimal
0 red 100 green 0 blue
#define DARKGREEN int(0/82048) + int(100/432)+ int(0/8)

or to code in binary
red green blue
#define TAN B111112048+B11000032+B10000