# An immediate mode operand merely serves as storage for data. An immediate A/B-mode in the current instruction sets the A/B-pointer to zero.

$ A direct mode operand indicates the offset from the program counter. A direct A/B-mode in the current instruction means the A/B-pointer is a copy of the offset, the A/B-number of the current instruction.

@ An indirect mode operand indicates the primary offset (relative to the program counter) to the secondary offset (relative to the location of the instruction in which the secondary offset is contained). An indirect A/B-mode indicates that the A/B-pointer is the sum of the A/B-number of the current instruction (the primary offset) and the B-number of the instruction pointed to by the A/B-number of the current instruction (the secondary offset).

< A predecrement indirect mode operand indicates the primary offset (relative to the program counter) to the secondary offset (relative to the location of the instruction in which the secondary offset is contained) which is decremented prior to use. A predecrement indirect A/B-mode indicates that the A/B-pointer is the sum of the A/B-number of the current instruction (the primary offset) and the decremented B-number of the instruction pointed to by the A/B-number of the current instruction (the secondary offset).

> A postincrement indirect mode operand indicates the primary offset (relative to the program counter) to the secondary offset (relative to the location of the instruction in which the secondary offset is contained) which is incremented after the results of the operand evaluation are stored. A postincrement indirect A/B-mode indicates that the A/B-pointer is the sum of the A/B-number of the current instruction (the primary offset) and the B-number of the instruction pointed to by the A/B-number of the current instruction (the secondary offset). The B-number of the instruction pointed to by the A/B-number of the current instruction is incremented after the A/B-instruction is stored, but before the B-operand is evaluated (for post-increment A-mode), or the operation is executed (for post-increment indirect B-mode).

* An indirect mode operand indicates the primary offset (relative to the program counter) to the secondary offset (relative to the location of the instruction in which the secondary offset is contained). An indirect A/B-mode indicates that the A/B-pointer is the sum of the A/B-number of the current instruction (the primary offset) and the B-number of the instruction pointed to by the A/B-number of the current instruction (the secondary offset).

{ A predecrement indirect mode operand indicates the primary offset (relative to the program counter) to the secondary offset (relative to the location of the instruction in which the secondary offset is contained) which is decremented prior to use. A predecrement indirect A/B-mode indicates that the A/B-pointer is the sum of the A/B-number of the current instruction (the primary offset) and the decremented B-number of the instruction pointed to by the A/B-number of the current instruction (the secondary offset).

} A postincrement indirect mode operand indicates the primary offset (relative to the program counter) to the secondary offset (relative to the location of the instruction in which the secondary offset is contained) which is incremented after the results of the operand evaluation are stored. A postincrement indirect A/B-mode indicates that the A/B-pointer is the sum of the A/B-number of the current instruction (the primary offset) and the B-number of the instruction pointed to by the A/B-number of the current instruction (the secondary offset). The B-number of the instruction pointed to by the A/B-number of the current instruction is incremented after the A/B-instruction is stored, but before the B-operand is evaluated (for post-increment A-mode), or the operation is executed (for post-increment indirect B-mode).

Not defined, unknown