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uint16_t cAlphaBlendA8RGB16(clr_a8rgb16_t fg, uint16_t bg)
{
/* RGB color mixing of "layer" with background data, using layer alpha channel
*
*/
	uint8_t alpha = fg.A;
	uint32_t fg = fg.rgb16;
	uint16_t bg;
	uint16_t result = 0;

  
  //The equation below is made from the original color mixing equation, to avoid using devision and fraction
  //This equation assumes that background is always not transparent.
  //Accuracy of this is very good. 90%of time the 8bits of the color components are the same.
  //Difference can maybe occur in the last LSB bit, but that does nearly nothing noticeable.
  //MY EXCEL sheet confirms all this.
  //This function should make the following equation (with order of execution)
  // ____III._______
  //			_______II.______
  //             ___I.___     __IV.__
  // ((fg*fg.A)+(256-fg.A)*bg)/256
  // The final devide by 256 is supplemented by a shifting to right by 8.
  //
  //Where fg is the layers color component (R, G or B), bg is the background color
  //Alpha is the alpha component of layer, bg has no alpha (non transparent)
  //result
  //%0: result (output)
  //%1: fg (input)
  //%2: bg (input)
  //%3: alpha (input)
	 __asm__ __volatile__ (
	 "MOVI %%a0, $0"
	 "wsr  %%a0, %%ACCLO"	//sets MAC16 ACC to 0
     "isync"
	 "MOVI %%a1, $256"		//puts 256 into reg A3
	 "MOVI %%a2, %3"		//loads a
	 "SUB %%a1, %%a1, %%a2"	//256-fg.A - I.
	 "MOVI %%a3, %1"			//loads fgcolor to A3
	 "MOVI %%a4, %2"			//loads bgcolor to A4
	 "MOVI %%a5, 31"		//Loads 0x11111b mask
	 //for B
	 "AND %%a6, %%a3, %a5"	//ands mask and fg for Blue components of layer, stores it in A6
	 "AND %%a7, %%a4, %a5"	//ands mask and bg for Blue components of background, stores it in A7
	 "MULA.AA.HH %%a2, %%a6"	//1st multiplication -  II.
	 "MULA.AA.HH %%a1, %%a7"	//2nd multiplication, result in ACCLO - III.
	 "SRLI %%a8, %%ACCLO, 8"	//store ACC result in A8 shifted right by 8 - IV.
	 //for G
	 "MOVI %%a0, $0"
	 "wsr  %a0, %%ACCLO"	//sets MAC16 ACC to 0
     "isync"
	 "MOVI %%a5, $63"
	 "SLLI %%a5, %%a5, 5"
	 "AND %%a6, %%a3, %a5"	//ands mask and fg for G components, stores it in A6
	 "AND %%a7, %%a4, %a5"	//ands mask and fg for G components, stores it in A7
	 "MULA.AA.HH %%a2, %%a6"	//1st multiplication
	 "MULA.AA.HH %%a1, %%a7"	//2nd multiplication, result in ACCLO
	 "SRLI %%a9, %%ACCLO, 8"	//store ACC result in A9 shifter right by 8
	 
	 //for R
	 "MOVI %%a0, $0"
	 "wsr  %a0, %%ACCLO"	//sets MAC16 ACC to 0
     "isync"
	 "MOVI %%a5, $31"
	 "SLLI %%a5, %%a5, 13"
	 "AND %%a6, %%a3, %a5"	//ands mask and fg for G components, stores it in A6
	 "AND %%a7, %%a4, %a5"	//ands mask and fg for G components, stores it in A7
	 "MULA.AA.HH %%a2, %%a6"	//1st multiplication
	 "MULA.AA.HH %%a1, %%a7"	//2nd multiplication, result in ACCLO
	 "SRLI %%a10, %%ACCLO, 8"	//store ACC result in A10 shifter right by 8
	 
	 //creating the resulted R5G6B5 format
	 //this section can be different to produce different end formats
	 "SRLI %%a8, %%a8, 3"
	 "SRLI %%a9, %%a9, 2"
	 "SLLI %%a9, %%a9, 5"
	 "SRLI %%a10, %%a10, 3"
	 "SLLI %%a10, %%a10, 13"
	 "ADD %%a8, %%a8, %%a9"
	 "ADD %3, %%a8, %%a10"
	 : "=r" (result)
	 : "r" (alpha), "r" (fg), "r" (bg)
	 : "%ACCLO", "%a0", "%a1", "%a2", "%a3", "%a4", "%a5", "%a6", "%a7"
	 );
}