Addressing modes are an aspect of the instruction set architecture in most central processing unit (CPU) designs. The various addressing modes that are...
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Real mode, also called real address mode, is an operating mode of all x86-compatible CPUs. The mode gets its name from the fact that addresses in real...
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X86 assembly language (redirect from X86-assembly language in protected mode)
in MMX) registers. The x86 processor also includes complex addressing modes for addressing memory with an immediate offset, a register, a register with...
57 KB (6,594 words) - 10:49, 22 May 2025
X86-64 (redirect from 64-bit compatibility mode)
64-bit mode, instructions are modified to support 64-bit operands and 64-bit addressing mode. The x86-64 architecture defines a compatibility mode that...
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access to the entire memory. Contrary to its name, it is not a separate addressing mode that the x86 processors can operate in. It is used in the 80286 and...
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In computing, protected mode, also called protected virtual address mode, is an operational mode of x86-compatible central processing units (CPUs). It...
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X86 (section Addressing modes)
in 64-bit mode, which is one of the two modes only available in long mode. The addressing modes were not dramatically changed from 32-bit mode, except that...
105 KB (10,776 words) - 12:49, 18 April 2025
ModR/M (section Special SIB byte addressing modes)
: 3-120 SIBMEM addressing. This addressing mode is used for instructions that perform a sequence of strided memory accesses. The effective address to use for...
17 KB (2,148 words) - 08:07, 26 September 2024
Z/Architecture (section Addressing modes)
two addressing modes supported by S/370-XA and ESA, a/Architecture has an extended addressing mode with 64-bit virtual addresses. The addressing mode is...
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WD16 (section Addressing modes)
destination addressing mode and register. If field I = 0, designated register contains the address of the operand, the equivalent of addressing mode (Rn). If...
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Flat memory model (redirect from Linear address mode)
memory addressing paradigm in which "memory appears to the program as a single contiguous address space." The CPU can directly (and linearly) address all...
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MOS Technology 6502 (section Addressing)
56 instructions with (possibly) multiple addressing modes. Depending on the instruction and addressing mode, the opcode may require zero, one or two additional...
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bits: n: Indirect addressing flag i: Immediate addressing flag x: Indexed addressing flag b: Base address-relative flag p: Program counter-relative flag...
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PDP-11 architecture (section Addressing modes)
word versus byte addressing). Two groups of six bits specify the source operand addressing mode and the destination operand addressing mode, as defined above...
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WDC 65C816 (section 24-bit addressing)
Direct page addressing uses an 8-bit address, which results in faster access than when a 16- or 24-bit address is used. Also, some addressing modes that offer...
29 KB (2,999 words) - 01:57, 13 April 2025
WDC 65C02 (section New addressing modes)
original 6502, fixes several problems, and adds new instructions and addressing modes. The power usage is on the order of 10 to 20 times less than the original...
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addressing mode. The base-plus-index and scale-plus-index forms of 32-bit addressing (encoded with r/m = 100 and mod ≠ 11) require another addressing...
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IBM System/370-XA (section 31-bit virtual addressing)
24-bit-addressing and 31-bit-addressing code include two new register-register call/return instructions which also effect an addressing mode change,...
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instruction types can use all addressing modes. It is "orthogonal" in the sense that the instruction type and the addressing mode may vary independently. An...
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Classful network (redirect from Classful addressing)
256 local addresses. The leading bit sequence 111 designated an at-the-time unspecified addressing mode ("escape to extended addressing mode"), which was...
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Indicating indirect addressing used separate opcodes, as opposed to using the addressing indication bits. When used, the address was constructed as normal...
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Direct memory access (redirect from Burst mode DMA)
64-bit mode of x86-64 CPU, or the Physical Address Extension (PAE), a 36-bit addressing mode. In such a case, a device using DMA with a 32-bit address bus...
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instances (XA/370), the instruction address was 31 bits plus a mode bit (24 bit addressing mode if zero; 31 bit addressing mode if one) for a total of 32 bits...
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word addresses, giving an address space of 218 36-bit words, approximately 1 megabyte of storage), not byte addressing. The range of addressing of memory...
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another specifies the addressing mode. An orthogonal instruction set uniquely encodes all combinations of registers and addressing modes. In telecommunications...
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Control register (redirect from Supervisor mode execution protection)
performed by control registers include interrupt control, switching the addressing mode, paging control, and coprocessor control. The early CPU lacked dedicated...
38 KB (1,706 words) - 18:26, 9 January 2025
I²C (redirect from I²C address)
resemblance to other I2C bus modes is limited to: the start and stop conditions are used to delimit transfers, I2C addressing allows multiple target devices...
77 KB (8,918 words) - 17:06, 18 May 2025
same MAC address. The IEEE 802 MAC address originally comes from the Xerox Network Systems Ethernet addressing scheme. This 48-bit address space contains...
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Central processing unit (section Privileged modes)
value that may be a processor register or a memory address, as determined by some addressing mode. In some CPU designs, the instruction decoder is implemented...
101 KB (11,424 words) - 06:24, 23 May 2025
addressing require the SIB byte, which encodes 2-bit scale factor as well as 3-bit index and 3-bit base registers. Depending on the addressing mode,...
12 KB (1,161 words) - 01:33, 1 September 2024