Initial data commit

Task/Four-bit-adder/Applesoft-BASIC/four-bit-adder.basic

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+100 S$ = "1100 + 1100 = " : GOSUB 400
+110 S$ = "1100 + 1101 = " : GOSUB 400
+120 S$ = "1100 + 1110 = " : GOSUB 400
+130 S$ = "1100 + 1111 = " : GOSUB 400
+140 S$ = "1101 + 0000 = " : GOSUB 400
+150 S$ = "1101 + 0001 = " : GOSUB 400
+160 S$ = "1101 + 0010 = " : GOSUB 400
+170 S$ = "1101 + 0011 = " : GOSUB 400
+180 END
+
+400 A0 = VAL(MID$(S$, 4, 1))
+410 A1 = VAL(MID$(S$, 3, 1))
+420 A2 = VAL(MID$(S$, 2, 1))
+430 A3 = VAL(MID$(S$, 1, 1))
+440 B0 = VAL(MID$(S$, 11, 1))
+450 B1 = VAL(MID$(S$, 10, 1))
+460 B2 = VAL(MID$(S$, 9, 1))
+470 B3 = VAL(MID$(S$, 8, 1))
+480 GOSUB 600
+490 PRINT S$;
+
+REM 4 BIT PRINT
+500 PRINT C;S3;S2;S1;S0
+510 RETURN
+
+REM 4 BIT ADD
+REM  ADD A3 A2 A1 A0 TO B3 B2 B1 B0
+REM  RESULT IN S3 S2 S1 S0
+REM  CARRY IN C
+600 C = 0
+610 A = A0 : B = B0 : GOSUB 700 : S0 = S
+620 A = A1 : B = B1 : GOSUB 700 : S1 = S
+630 A = A2 : B = B2 : GOSUB 700 : S2 = S
+640 A = A3 : B = B3 : GOSUB 700 : S3 = S
+650 RETURN
+
+REM FULL ADDER
+REM  ADD A + B + C
+REM  RESULT IN S
+REM  CARRY IN C
+700 BH = B : B = C : GOSUB 800 : C1 = C
+710 A = S : B = BH : GOSUB 800 : C2 = C
+720 C = C1 OR C2
+730 RETURN
+
+REM HALF ADDER
+REM  ADD A + B
+REM  RESULT IN S
+REM  CARRY IN C
+800 GOSUB 900 : S = C
+810 C = A AND B
+820 RETURN
+
+REM XOR GATE
+REM  A XOR B
+REM  RESULT IN C
+900 C = A AND NOT B
+910 D = B AND NOT A
+920 C = C OR D
+930 RETURN