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- 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.