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7 years, 11 months ago.
Sharp Memory Colour LCD
I'm trying to use my existing library to work the colour Memory LCD, but got a bit stuck. Not sure whether it is possible to change the code below or to try a different approach.
The problem is I need to set three bits to generate the colours Red, Green, Blue. The mono displays only have one bit to set.
The display is arranged as 128 x128 pixels, however the x range is three times this (384) to accommodate the three colour bits.
single bit code snip
// Existing Color definitions for mono
#define White 0xFF
#define Black 0X00
// Color definitions for colour bits
//#define Black 0x00
#define Blue 0X01
#define Green 0X02
#define Cyan 0X03
#define Red 0X04
#define Magenta 0X05
#define Yellow 0X06
//#define White 0X07
void SharpLCD::pixel(uint16_t x, uint16_t y, uint8_t colour) {
uint8_t swapx = 7 - ((uint16_t)x & 0x07);
x = ((uint16_t)x & 0xFFF8) | swapx;
// determine if row has pixel changes
bool change = ((pixelBuffer[((y * DISPLAY_WIDTH) + x) / DISPLAY_BUFFER_TYPE_SIZE] & (1 << (x % DISPLAY_BUFFER_TYPE_SIZE)))
!= ((colour & 0x01) << (x % DISPLAY_BUFFER_TYPE_SIZE)));
if(change) {
// xor operation
pixelBuffer[((y * DISPLAY_WIDTH) + x) / DISPLAY_BUFFER_TYPE_SIZE] ^= (1 << (x % DISPLAY_BUFFER_TYPE_SIZE));
// update pixel change status of this line
RowState[y / DISPLAY_BUFFER_TYPE_SIZE] |= (1 << (y % DISPLAY_BUFFER_TYPE_SIZE));
}
}
I have got the display working by setting the x (display width) to 384, displays black/white characters and graphics but they are a third of the width they should be. I have seen an example video of the display working on the net (Arduino), but can't find any code examples.
Any help would be appreciated.
Many thanks
Paul
1 Answer
7 years, 11 months ago.
Data sheet?
found this link
https://github.com/pkourany/Adafruit_SharpMem
The main difference between the monochrome and color displays is the bit-packing that is required since now 1 pixel = 3 bits. So each line is 48bytes (128 3-bit pixels). The only trick is now the 3-bit boundaries don't match up with byte boundaries. No biggy but just a pain. A fully buffered screen will need 6,144bytes of RAM