Generic Addressing Modes
03/21/96
Absolute: | To a specific address location. Sometimes referred to as General Addressing | Immediate: | The method of loading the specific value(s) following the Op-Code. |
Relative: | A location that is forward or backward, relative to, or from, the current location. |
Indirect: | To a specific address location, that is identified as an address value, contained within another address location (as an Indirect Location) |
Register: | To a specific address location, specified by the contents of a register. |
Indexed: | A specific form of Register Addressing, with provision for an additive "Offset" of the specified address, allowing variable "Indexing" from the "Base Address" within the Index-Register. |
Pre-Indexed: | A combination addressing method, incorporating Indexed Addressing prior to the use of Indirect Addressing. |
Post-Indexed: | A combination addressing method, incorporating Indexed Addressing after the use of Indirect Addressing. |
Page: | A form of addressing related to specific "Pages" or "Blocks" of memory. |
Base Page: | Page Addressing restricted to specifically the "Base-Page" of memory. |
Extended: | A form of memory addressing that allows for an extension beyond the normal range of addressing. |
Internal: | Any form of activity that is only within the CPU, and does not affect outside devices or memory. |
I/O: | Address Lines are used for "Device Address" in all cases. |
Port Mapped: | I/O Device Addressing in conjunction with "IOREQ" type of signals. |
Memory Mapped: | I/O Device Addressing in conjunction with conventional "MREQ" type of signals. |