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Questions tagged [microcoding]

Microcoding involves writing the code and data structures that make up the machine code instructions in processors.

Microcode is a layer of hardware-level instructions or data structures involved in the implementation of higher level machine code instructions in central processing units, and in the implementation of the internal logic of many channel controllers, disk controllers, network interface controllers, network processors, graphics processing units, and other hardware. wikipedia

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Is there a programming language "below" Assembly?

Is there a programming language "below" Assembly?
Tal
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How does machine code communicate with processor?

Let's take Python as an example. If I am not mistaken, when you program in it, the computer first "translates" the code to C. Then again, from C to assembly. Assembly is written in machine code. (This is just a vague idea that I have about this so…
JoeSlotsky
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What is a microcoded instruction?

I have seen a lot of literature referencing microcoded instructions. What are these and why they are used?
user6754053
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Do x86/x64 chips still use microprogramming?

If I understand these two articles, the Intel architecture, at it's lowest level, has transitioned to using RISC instructions, instead of the the traditional CISC instruction set that Intel is known…
Sajee
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How can memory destination BTS be significantly slower than load / BTS reg,reg / store?

In the general case, how can an instruction that can take memory or register operands ever be slower with memory operands then mov + mov -> instruction -> mov + mov Based on the throughput and latency found in Agner Fog's instruction tables (looking…
Noah
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CPU: Program inside CPU that determines exact principal of instructions (?!)

At Computer Science lecture we’ve been told that there’s a special code (lower that assembler) that determines behavior of CPU which is written inside CPUs ROM. It was meant that is determines what exactly every instruction in boolean logic means……
Ben Usman
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Microcode terminology: are there names for different "styles" of microcode?

I've been looking at microcode and wondered about terminology. The "classic" use of microcode is to replace the processor control logic with microcode to generate the processor control signals. But there are some systems that go much further and…
Ken Shirriff
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Microprogramming in MIPS

I am learning about micro programming and am confused as to what a micro-instruction actually is. I am using the MIPS architecture. My questions are as follows Say for example I have the ADD instruction, what would the micro-instructions look like…
microProgQuestions
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Fetch Microoperations for CALL

I am trying to understand how the fetch cycle would be written in micro-operations for a CALL instruction of 32 bits were to be fetched by the cpu. MAR is 16 bits wide MDR is 8 bits wide PC is 16 bits wide IR is 16 bits wide Temp registers are 16…
Jim Newtron
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How do I use microprogramming to modify the instruction set architecture of an Intel CPU?

Suppose I wanted to modify the implementation of an existing instruction. For instance, suppose I wanted to change the microcode that is executed by my processor when a "mov" instruction is executed after being fetched and decoded. How would I do…
James
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What exactly is a machine instruction?

The user's program in main memory consists of machine instructions and data. In contrast, the control memory holds a fixed microprogram that cannot be altered by the occasional user. The microprogram consists of microinstructions that specify…
james
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What is the difference between bytecode and microcode?

I was reading on wikipedia about machine code, microcode and bytecode. It seems that microcodes are something more low-level than machine code, while bytecodes seem to be more high-level. I didn't realy get how something can be more low-level than…
Gabriele Scarlatti
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Low Level GUI Programming

How are gui's created at the lowest level? In Java, one may type in a JFrame method and create a window. At some point, this window must be coded pixel by pixel. Is this done by assembly, machine code, or microcode in the processor?
user3259479
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Intel microcode update version number meaning

I need having two microcode version for the same CPU to understand which one is newer (includes fixes from another). Microcode version is not monotonous so it can decrease with an update. Based on what I have seen microcode version is a number less…
Anton Zyablitskiy
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LED not glowing on off by push button with PIC18f2455 in Proteus

I searched around much to glow the LED on pressing PUSH Button in Proteus . But LED glows on its on and do not turn Off on pressing Push Button in Proteus. I am working on Simulation with PIC18F2455 and here is the MicroC code. void main() { …
Nabeel Raza
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