User manual
Hardware Description
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The same scheme as above is used in the 16-bit color resolution configuration, although
in this case the frame buffer entry is output directly to the display instead of indexing a
palette table.
In the 24-bit color resolution configuration, each frame buffer entry consists of one byte
for each color, see Table5.7, “LCDC 24 bit memory organization”.
Bit[23..16] Bit[15..8] Bit[7..0]
Blue[7..0] Green[7..0] Red[7..0]
Table5.7.LCDC 24 bit memory organization
If the LCD Module has lower color resolution (fewer bits per color component), only the
most significant bits of each component are used.
The Linux frame buffer driver offers a function which returns the information about the
frame buffer structure including the assignment of each frame buffer bit to a color channel
bit. It is recommended that graphics software uses this function in order to achieve a
correct color representation.
5.32. Touch Screen ADC Controller (ADC)
The StampA5D3x has a 12-bit Analog-to-Digital Converter, which includes a 4-wire or 5-
wire resistive touchscreen controller. It integrates a 12-to-1 analog multiplexer, making
analog-to-digital conversions of 12 analog lines possible. The conversions extend from 0V
to the voltage carried on pin ADVREF and has configurable timings.