section 7 - Index of

6.3.5.3 Special Addressing ModesThe special addressing modes do not use specific registers to specify an effectiveaddress. These modes specify the operand or the operand address in a field of theinstruction, or they implicitly reference an operand. Figure examples are given for each ofthe special addressing modes discussed in the following paragraphs.6.3.5.3.1 Immediate DataClassified as a program reference, this addressing mode requires one word of instructionextension containing the immediate data. Figure 6-7 shows three examples. Example Amoves immediate data to register AO without affecting A 1 or A2. Examples Band C zerofill register AO and sign extend register A2.-6.3.5.3.2 Absolute AddressThis addressing mode requires one word of instruction extension containing the absoluteaddress. Figure 6-8 shows that MOVE Y:$5432,BO copies the contents of address $5432into BO without changing memory location $5432, register B1, or register B2. Thisaddressing mode is classified as both a memory reference and program reference. The16-bit absolute address is stored in the 16 LSBs of the extension word; the eight MSBsare zero filled.6.3.5.3.3 Immediate ShortThe 8- or 12-bit operand, which is in the instruction operation word, is classified as a programreference. The immediate data is interpreted as an unsigned integer (low-orderportion) or signed fraction (high-order portion), depending on the destination register. Figure6-9 shows the use of immediate short addressing in four examples.6.3.5.3.4 Short Jump AddressThe operand occupies 12 bits in the instruction operation word, which allows addresses$OOOO-$OFFF to be accessed (see Figure 6-10). The address is zero extended to 16 bitswhen used to address program memory. This addressing mode is classified as a programreference.6.3.5.3.5 Absolute ShortThe address of the operand occupies six bits in the instruction operation word, allowingaddresses $0000-$003F to be accessed (see Figure 6-11). Classified as both a memoryreference and program reference, the address is zero extended to 16 bits when used toaddress an operand or program memory.