Microcontroller Instruction Set. For interrupt response time information, refer to the hardware description chapter. Note: 1. Operations on SFR byte address Instruction Set. ♢ Introduction. ♢ CIP architecture and memory organization review. ♢ Addressing modes. ➢ Register addressing. ➢ Direct addressing. Instruction hex code. MOVE with immediate data. Hex. Bytes Instruction. 2. MOV A, #immediate. 3. MOV direct, #immediate. 2. MOV @R0, #.
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Even the PC and the stack pointer could be affected by the ordinary instructions using all of the ordinary data modes. It maintained some degree of non-orthogonality for the sake of high code density even though this was derided as being ” baroque ” by some computer scientists [ who? Processor register Register file Memory buffer Program counter Stack.
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Instruction Set Manual: Opcodes
The bit extension of this architecture that was introduced with thewas somewhat more orthogonal despite keeping all the instructions and their extended counterparts. This article possibly contains original research.
Statements consisting only of original research should be removed. In many CISC computers, an instruction could access either registers or memory, usually in several different ways.
This section does not cite any sources. Articles that may contain original research from November All articles that may contain original research Articles needing additional references from April All articles needing additional references Articles with multiple befelhssatz issues Articles needing additional references from April All articles with specifically marked weasel-worded phrases Articles with specifically marked weasel-worded phrases from April Perhaps some of the bits that were used to express the fully orthogonal instruction set could instead be used to express more virtual address bits or select from among more registers.
In the late s research at IBM and similar projects elsewhere demonstrated that the majority of these “orthogonal” addressing modes were ignored by most programs. Since addressing modes were identical, this made 13 electronic addressing modes, but as in the PDP, the use of the Stack Pointer R14 and Program Counter R15 created a total of over 15 conceptual addressing befwhlssatz with the assembler program translating the source code into the actual stack-pointer or program-counter based addressing mode needed.
Conversely, data must be in registers before it can be operated upon by the other instructions in the computer’s instruction set. The binary-compatible Z80 later added prefix-codes to escape from this 1-byte limit and allow for a more powerful instruction set. An orthogonal instruction set does not impose a limitation that requires a certain instruction to use a specific register.
Through the use of the Stack Pointer R6 and Program Counter R7 as referenceable registers, there were 10 conceptual addressing modes available. Motorola’s designers attempted to make the assembly language orthogonal while the underlying machine befehlssarz was somewhat less so.
Single-core Multi-core Manycore Heterogeneous architecture. Please help improve this section by adding citations to reliable sources.
Designers of RISC architectures strove to achieve a balance that they thought better. The 8-bit Intel as well as the and microprocessor was basically a slightly extended accumulator-based design and therefore not orthogonal. This article needs additional citations for verification.
It is ” orthogonal ” in the sense that the instruction type and the addressing mode vary independently. Please help improve it or discuss these bedehlssatz on the talk page. Branch prediction Memory dependence prediction. Every integer instruction could operate on either 1-byte or 2-byte integers and could access data stored in registers, stored as part of the instruction, stored in memory, or stored in memory and pointed to by addresses in registers.
This resulted in 16 logical addressing modes 0—15however, addressing modes 0—3 were “short immediate” for immediate data of 6 bits or less the 2 low-order bits of the addressing mode being the 2 high-order bits of the immediate data, when prepended to the remaining 4 bits in that data-addressing byte. April Learn how and when to remove this template message. An assembly-language programmer or compiler writer had to be mindful of which operations were possible on each register: This was largely due to a desire to keep all opcodes one byte long.
A fully orthogonal architecture may not be the most “bit efficient” architecture. The same basic idea was employed for the Intelalthough, to allow for more radical extensions, binary -compatibility with the was not attempted here. Unsourced material may be challenged and removed.
At the bit level, befehlsstaz person writing the assembler or debugging machine code would clearly see that symbolic instructions could become any of several different op-codes. This article has multiple issues.
Orthogonal instruction set
In these architectures, only a very few memory reference instructions can access main memory and only for the purpose of loading data into befehlsastz or befehossatz register data back into main memory; only a few addressing modes may be available, and these modes may vary depending on whether the instruction refers to data or involves a transfer of control jump.
Instruction processing Instruction set architectures. From Wikipedia, the free encyclopedia. This compromise gave almost the same convenience as a truly orthogonal machine, and yet also gave the Beffhlssatz designers freedom befehlssata use the bits in the instructions more efficiently than a purely orthogonal approach might have.
Views Read Edit View history. Tomasulo algorithm Reservation station Re-order buffer Register renaming. November Learn how and when to remove this template message. In computer engineeringan orthogonal instruction set is an instruction set architecture where all instruction types can use all addressing modes. Learn how and when to remove these template messages. The Befehlssats of Computer Organization and Architecture.
However, the encoding-strategy used still shows many traces from the and and Z80 ; for instance, single-byte encodings remain for certain frequent operations such as push and pop of registers and constants, and the primary accumulator, eaxemploy shorter encodings than the other registers on certain types of operations; observations like this are sometimes exploited for code optimization in both compilers and hand written code.