PIPPIN Instruction Set
Program 1: Add 2 numbers
Program 2: Count down loop

Note:
The purpose and intent of the AND instruction is not clear and is not included in the following table. The PIPPIN simulator included on the CD and at the authors' Web site places 0 in the accumulator regardless of the input to AND.

Opcode | Operand		Assembly Instruction	Description
Binary	Hex
00000000 bbbbbbbb	00 XX	ADD X	Add contents of referenced memory address to contents of accumulator. Address Mode = Direct
			Example:   Add value stored at memory address 128 (10000000 binary, 80 hex, variable W) to contents of accumulator.
			00000000 10000000	00 10	ADD W
00010000 bbbbbbbb	10 XX	ADD #n	Add immediate value to contents of accumulator. Address Mode = Immediate
			Example:   Add the number 45 (00101101 binary, 2D hex) to accumulator:
			00010000 00101101	10 2D	ADD #45
00000001 bbbbbbbb	01 XX	SUB X	Subtract contents of referenced memory address from contents of accumulator. Address Mode = Direct
			Example:   Subtract value stored at memory address 129 (10000001 binary, 81 hex, variable X) from accumulator.
			00000001 10000001	01 11	SUB X
00010001 bbbbbbbb	11 XX	SUB #n	Subtract immediate value from contents of accumulator. Address Mode = Immediate
			Example:   Subtract the number 27 (00011011 binary, 1B hex) from accumulator:
			00010001 00011011	11 1B	SUB #27
00000010 bbbbbbbb	02 XX	MUL X	Multiply contents of accumulator by 8-bit value stored at referenced memory address. Address Mode = Direct
			Example:   Multiply accumulator by value stored at memory address 130 (10000010 binary, 82 hex, variable Y).
			00000010 10000010	02 12	MUL Y
00010010 bbbbbbbb	12 XX	MUL #n	Multiply contnets of accumulator by immediate value. Address Mode = Immediate
			Example:   Multiply accumulator by the number 5 (00000101 binary, 05 hex):
			00010010 00000101	12 05	MUL #5
00000011 bbbbbbbb	03 XX	DIV X	Divide contents of accumulator by 8-bit value stored at referenced memory address. Address Mode = Direct
			Example:   Divide accumulator by value stored at memory address 131 (10000011 binary, 83 Hex, variable Z).
			00000011 10000011	03 13	DIV Z
00010011 bbbbbbbb	13 XX	DIV #n	Divide contnets of accumulator by immediate value. Address Mode = Immediate
			Example:   Divide accumulator by the number 10 (00001010 binary, 0A hex):
			00010011 00001010	13 0A	DIV #10
00000100 bbbbbbbb	04 XX	LOD X	Load the accumulator with the 8-bit value stored at referenced memory address. Address Mode = Direct
			Example:   Place value stored at memory address 132 (10000100, 84 Hex, variable T1) into accumulator.
			00000011 10000011	03 13	DIV Z
00010100 bbbbbbbb	13 XX	LOD #n	Load the accumulator with an immediated value. Address Mode = Immediate
			Example:   Place the number 100 (01100100 binary, 64 hex) into accumulator.
			00010100 01100100	14 64	LOD #100
00000101 bbbbbbbb	05 XX	STO X	Store the contents of the accumulator into the referenced memory address. Address Mode = Direct
			Example:   Save value of accumulator in memory address 133 (10000101 binary, 85 hex, variable T2).
			00000101 10000101	05 15	STO T2
00001001 00000000	09 00	NOT	If the accumulator contains 0 then set the accumulator to 1; otherwise set the accumulator to 1. Assume any non-zero value = TRUE and 0 = FALSE; NOT inverts the "truth" of the accumulator.
00001010 bbbbbbbb	0A XX	CPZ X	Compare X with Zero; if the contents of the referenced memory address = 0, set the accumulator to 1 (TRUE), otherwise set accumulator to 0 (FALSE). e.g. TRUE or FALSE: "Does X = 0? Address Mode = Direct
			Example:   Set the accumulator to 1 (TRUE) or 0 (FALSE) depending on whether the value in memory address 129 (10000001 binary, 81 Hex, variable X) = 0.
			00001010 10000001	0A 11	CPZ X
00001011 bbbbbbbb	0B XX	CPL X	Compare X with Zero; if the contents of the referenced memory address is LESS than 0, set the accumulator to 1 (TRUE), otherwise set accumulator to 0 (FALSE). e.g. TRUE or FALSE: "Is X < 0? Address Mode = Direct
			Example:   Set the accumulator to 1 (TRUE) or 0 (FALSE) depending on whether the value in memory address 130 (10000010 binary, 82 Hex, variable Y) < 0.
			00001011 10000010	0B 10	CPL Y
00001100 bbbbbbbb	0C XX	JMP n	Unconditional Jump: Set PC to n and execute instruction at that address.
			Example:   Execute instruction at memory address 14 (00001110 binary, 0E hex).
			00001110 00001110	0C 0E	JMP 14
00001101 bbbbbbbb	0D XX	JMZ n	Conditional Jump: Set PC to n and execute instruction at that address IF the accumulator = 0; otherwise go to next instruction.
			Example:   Execute instruction at memory address 4 (00000100 binary, 04 hex) IF the accumulator is 0.
			00001101 00000100	0D 04	JMZ 4
00001110 00000000	0E 00	NOP	No operation; do nothing and go to next instruction.
00001111 00000000	0F 00	HLT	Halt execution; Control Unit does not fetch any more instructions.

PIPPIN memory after program execution:

        00  01  02  03  04  05  06  07  08  09  0A  0B  0C  0D  0E  0F

    00  14  03  05  80  14  07  05  81  00  80  05  82  0F  00  00  00
    01  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00
    ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..
    07  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00

    08  03  07  0A  00  00  00  00  00  00  00  00  00  00  00  00  00
    09  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00
    ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..  ..
    0F  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00