Retro Watch Company

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The library is very much in its infancy…GitHub will be coming online soon but here is a taste of how you might do a simple software only framebuffer:

[code] #include <zephyr.h> #include <device.h> #include <devicetree.h>

#include <math.h> #include <string.h>

the retro watch sdk includes #include “lcd.h” #define SCREEN_WIDTH 240 #define SCREEN_HEIGHT 240 convert 565 rgb into 16 bit word and swap bytes for lcd uint16_t rgb(int r, int g, int b) {

uint16_t c = (((r) << 11) | ((g) << 5) | (b));

return ((c >> 8) & 0xFF) | ((c & 0xFF) << 8);

}

void main(void) {

uint16_t *frame_buffer;

printk("hello cruel world\n");

//initialize the lcd
lcd_configure();

while(1)
{
	//swaps buffers and DMA previous buffer to LCD
	lcd_update_screen();

	//get new back buffer
	frame_buffer = lcd_get_buffer();

	for(int ix = 0; ix < SCREEN_WIDTH; ix++)
	{	
		for(int iy = 0; iy < SCREEN_HEIGHT; iy++)
		{
			//fill frame buffer with a simple xor pattern
			frame_buffer[ix + iy * SCREEN_WIDTH] = rgb((ix ^ iy)>>3, iy>>2, ix>>3);
		}
	}
}

}

[/code]