Add_odds

;Calculate the sum of series of odd numbers from the list of numbers. The length
;of the list is in memory location 2200H and the series itself begins from memory 
;location 2201H. Assume the sum to be 8 bit number so you can ignore carry and store 
;the sum at memory location 2210H.

JMP START 

START:  MVI A,05; LENGTH OF LIST
	STA 2200;

	; ELEMENTS OF LIST:

	MVI A,01;
	STA 2201;
	STA 2203;

	MVI A,03;
	STA 2202
	STA 2204

	MVI A,02;
	STA 2205

	; ACTUAL PROGRAM ;

	LXI H,2201; LOAD FIRST ELEMENT ADDRESS

	LDA 2200;
	MOV B,A; STORE NUMBER OF ELEMENTS IN B

	MVI C,0; 
	LXI D,0; CLEAR DE PAIR
	MVI A,0; CLEAR A
	DCR B;

REPEAT: MOV A,M; MOVE CONTENTS OF MEMEORY TO A
	CALL CHECK; CHECK IF ODD
	JNC DONTADD;
	MOV A,C;
	ADD M;
	MOV C,A;

DONTADD: INX H; INCREMENT HL PAIR
	DCR B; DEC COUNTER
	JNZ REPEAT
	MOV A,C;
	STA 2210;
	HLT

CHECK:  CPI 02; COMPARE WITH 2
	JP ISBIG; 
		CPI 01; COMPARE WITH 1
		JNZ EXIT; IF FLAG NOT 0 THEN A IS 0
			STC; ELSE SET CARRY TO INDICATE ODD
			JMP EXIT

ISBIG:  SUI 02; A-2=>A
	JZ EXIT; IS A BECOMES 0 THEN EVEN
	JP JUMP;
		STC; ELSE SET CARRY TO INDICATE ODD
		JMP EXIT; EXIT
JUMP:	JMP ISBIG

EXIT:	RET