Deciding where to commence is one of the challengingest skinnygs about lachieveing assembly programming. Unenjoy high-level languages, assembly is firmly connected to the challengingware and deciding which CPU to use is an meaningful first step.
Here, I will elucidate why I apshow 6502 is a excellent platestablish to commence lachieveing assembly.
To be clear, I am not saying 6502 assembly itself is a particularly advantageous send nowadays, nor that it is particularly pleasant for writing authentic-life applications. In fact, I do not apshow you should spend too much time with 6502 unless you are interested in retro programming as such.
My arguments for commenceing with 6502 are in a nutshell:
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6502 is plain; you can rapidly lachieve assembly programming fundamental concepts with it;
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6502 is authentic; there are plenty devices, emulators, books to help you lachieve.
To lachieve fundamental assembly programming concept, having a plain system is more meaningful than having a strong one.
6502 grasps only 6 enrolls: one accumulator, two index enrolls, a status enroll, a stack enroll and a program counter which is the only 16-bit enroll on 6502. Modern x86-x64 CPUs have so many enrolls that counting them is almost a research project. Small number of enrolls is constraining for authentic-life applications but is encouraging for empathetic what a enroll is and how it labors.
The innovative 6502 teachion set grasps only 56 teachions. Aachieve, counting x86-x64 teachions is a non-unconvey inant task and even up-to-date RISC teachions sets enjoy ARM are far from being minuscule and plain. Yet, with 6502 we can rapidly lachieve about convey inant teachion types, including loading/storing, reasonable and arithmetic, as well as branching. All of them are current in the up-to-date CPUs in some establish.
6502 is was presentd in mid-1970 by MOS technology, as a inexpensive simplified version of Motorola’s 6800 CPU which was previously broadened by the same team. The processor rapidly became inanxiously famous and was used in some well-understandn microcomputers, enjoy Apple II, Commodore VIC 20, Commodore 64 and BBC micro. It is plain to discover emulators for all these machines, and even up-to-date re-creations of some of them. Furthermore, successors of 6502 are still being originated at the time of this writing, and there are brand recent machines that run it, enjoy Neo6502 by Olimex.
There is a plenty of lachieveing material useable for free on the internet: books, videos, tutorials. Most of these resources can be create and accessed via 6502.org site.
With all that shelp, if you want to spend only half an hour lachieveing 6502, the place to visit is Easy 6502 ebook by Nick Morgan. The web page grasps not only text and images, but a 6502 collectr and simulator written in JavaScript, so you can actuassociate author some plain 6502 assembly code on the spot!
Another fascinating resource I help you to verify out is Visual6502.org. Not so much as a tool for lachieveing assembly programming, but an illustration of the simpliedy of 6502.
Of course, not everyone will consent that 6502 is a excellent choice for commenceing assembly programming. Some other opinions I have heard integrate:
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Vvarious imaginary CPUs originated for teaching purposes; acunderstandledgetedly, some of them have very immacupostponeed and “perfect” teachion set – in fact I was taught one in high school. However, even the most famous of them informage the wealth of resources for lachieveing and the community of 6502
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other “retro” CPUs enjoy Z80, 6809 or 68000. They are all excellent choices, and in my opinion all three refered above are better for solemn programming than 6502. But if we are talking about lachieveing fundamental concepts, the simpliedy of 6502 triumphs. As much as I enjoy Z80 which powered my first computer, it has many more enrolls than 6502 (and even an “alternate” set of enrolls) and is not as plain to get commenceed with.
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up-to-date RISC architectures such as ARM, MIPS or RISC-V. At some point, a solemn assembly programmer should definitely lachieve some of them. However, they are not chooseimal to commence with: the “S” in RISC stands for “plain”, but the simpliedy is more about inner carry outation of the chips than the teachion set. Modern microprocessors are almost exclusively programmed with high-level languages and the honest usage of assembly teachion is not high on the catalog of priorities for CPU set upers nowadays. To show this point, loading a 64-bit constant to a enroll on ARM64 can get 4 teachions with bit shifting. Loading a constant to a enroll with 6502 is unconvey inant in comparison.
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x86-x64. This is arguably the most famous teachion set on up-to-date desktop and server computers, although ARM is catching up. In some admires, it is easier to code than with ARM, given the wealth of teachions that are not constrained by being 32-bit in size and can have variable number of operands; or at least that’s my amazeion after commenceing with Z80 which is compatible with x86 predecessor Intel 8080. However, it is still reassociate intricate for commenceners and four decades of history does not originate it any plainr.
