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Instructions

   

HLT
Ends the program execution. Register and memory values are not changed. After setting the instruction pointer to another address the programm execution can be resumed.
LAD
Loads the accumulator with the operand or the value described by the addressing mode.
SPI
Stores the accumulator to the memory address described by the addressing mode.
ADD
Adds the operand described by the addressing mode to the accumulator. This operation obeys signs. There is no information if an overflow occured.
SUB
Subtracts the operand described by the addressing mode from the accumulator. This operation obeys signs. There is no information if an overflow occured.
MUL
Multiplies the operand with the accumulator and stores the result in the accu. This operation obeys signs. There is no information if an overflow occured.
DIV
Divides the accumulator with the operand and stores the result in the accu. This is an integer division and the remainder is stored in the SWAP Register. This operation obeys signs. There is no information if an overflow occured.
JMP
Jumps to the given address.
JEZ
Jumps to the given address if the accumulator is equal zero.
JGZ
Jumps to the given address if the accumulator is greater or equal zero.
JLZ
Jumps to the given address if the accumulator is lower zero.
SWAP
Swaps the accumulator and the help register.
JSR
Jumps to the given address. The address of the following instruction is pushed on the stack.
RET
Pops an address from the stack and continues the program execution at that address.

The arithmetic instructions always hold their result in the accumulator.