Assembler programming on the Raspberry Pi
Assembler on Pi
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Talk to your Raspberry Pi in its native assembler language.
Assembler programs run directly on the computer's hardware, which means they can reach nearly the maximum achievable speed of execution. Because assembler program code is very low level, writing the code is more complicated, but it is still the best choice for some tasks, especially on a computer such as the Raspberry Pi with its limited resources. Before you can start creating programs, however, you need to plumb the depths of the CPU and peripheral architecture.
Machine Code
To begin, it makes sense to clarify some terms. The CPU only understands machine code – zeros and ones or, more precisely, voltage levels that represent zeros and ones. Each command in machine code has a human-readable abbreviation that is easy to remember. These abbreviations are known as mnemonics and act as assembler commands. Assembler code is specific to a CPU architecture, which means that code for a Raspberry Pi (ARM) will not run on a PC (x86).
Programming in assembler on the Raspberry Pi can be approached in two ways: First, you can create an image in which you package the code and then boot the small-board computer (SBC) from that image to run the program. In other words, you degrade the Raspberry Pi to a microcontroller. With this method, the Pi runs without an operating system. Although you have full access to everything, you don't even get a shell.
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