The PIPPIN User's Guide - PIPPIN Instruction Set

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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.