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Addressing Modes

 
Direct via Address
Form: @address, MOD: 0xx.
The first bit of the MOD bits is zero. The remaining bits are the highest bits of the address. A single-word instruction has a addressrange of 10 bits. In a double-word instruction the remaining MOD bits are ignored.
Direct with Operator
Form: #operator, MOD: 100.
Values from -128 to +127 are stored in a single-word instruction. For higher values a double-word instruction is used. Those bits not belonging to the maximum addressing width of the cpu are ignored.
Relative to the Instruction Pointer
Form: address, MOD: 101
The address is relative to the instruction pointer. There are 8 bits usable for single-word instructions (-128 to 127). For greater offsets a double-word instruction will be used. Die Adresse wird relativ zum Those bits not belonging to the maximum addressing width of the cpu are ignored.
Indirect Address
Form: (address), MOD: 110.
The real address is found via the address given as a parameter. There are 8 bits usable for single-word instructions (-128 to 127). For greater offsets a double-word instruction will be used. Die Adresse wird relativ zum Those bits not belonging to the maximum addressing width of the cpu are ignored.
Relative to the Indexregister
Form: %address, MOD: 111.
The address is relative to the indexregister. There are 8 bits usable for single-word instructions (-128 to 127). For greater offsets a double-word instruction will be used. Die Adresse wird relativ zum Those bits not belonging to the maximum addressing width of the cpu are ignored.

next up previous contents
Next: Instructiontable Up: Instructions Previous: Indexinstructions
Markus Hennecke
9/14/2003