What is the history of why bytes are eight bits?
First a bit of clarification: Octets (8-bit units) are not really a fundamental unit in modern computer architectures. At least not any more fundamental than other powers of two - 2, 4, 16, 32, 64, 128 etc. Octets were the fundamental unit for 8-bit processors (hence the name!), but modern architectures typically work with larger bit-sets ...
What is the advantage of choosing ASCII encoding over UTF-8?
ANSI can be many things, most being 8 bit character sets in this regard (like code page 1252 under Windows). Perhaps you were thinking of ASCII which is 7-bit and a proper subset of UTF-8. I.e. any valid ASCII stream is also a valid UTF-8 stream.
8 bit and 1 byte, is this a valid question to be asked?
A) 1 bit. B) 4 bit. C) 8 bit. D) 1 byte. What is the smallest unit of memory C or C++ use? A) 1 bit. B) 4 bit. C) 8 bit. D) 1 byte. The answer to both are D, but I am thinking if this is inappropriate. EDIT: 1 byte is not necessarily 8 bits on some systems. See this StackOverflow post.
Is using 64 bit integers (long long) faster than less bits ones?
2020年6月6日 · C and C++ use 32 bit int because otherwise there is no 32 bit type available (char = 8 bit, short = 16 bit or you have no 16 bit type, int must be 32 bit or you have no 32 bit type). Swift on 64 bit devices has Int = 64 bit, but also has Int8, Int16, Int32 and Int64 so the problem that C has is avoided. –
The size of a byte in platform independent software
2021年12月9日 · I have once seen source code written for sixteen bit bytes. Some DSP processor, 20 years ago. Since storing an 8 bit character in a 16 bit byte is inefficient, they had a library handling strings with two characters stored in one byte. You can “safely” assume a byte is eight bits. If it isn’t, you may have to do a lot of extra work.
bit - Why are CPUs' datapaths multiple of 8? - Software …
2022年3月30日 · The data bus size being multiples of 8 is linked directly to the 8-bit byte. The address bus is different: implementers provide as many bits as needed to access all the memory the processor supports. In the case of the Pentium Pro, it …
Why is 2^16 a "special" number? [closed] - Software Engineering …
There were 16-bit commands and 16-bit memory addresses. A lot of systems/compilers still use 16 bits for integers. So, (2 16 - 1) is special because it is the largest number that a 16-bit (unsigned) integer can hold and the largest memory address that a 16-bit architecture can access.
How to align on both word size and cache lines in x86
2018年8月22日 · Align 8-bit data at any address [don't understand this] Align 16-bit data to be contained within an aligned four-byte word; Align 32-bit data so that its base address is a multiple of four; Align 64-bit data so that its base address is a multiple of eight; Align 80-bit data so that its base address is a multiple of sixteen
In C++, Why do bitwise operators convert 8 or 16 bit integers to …
2020年5月27日 · I was trying to make an 8bit mask, and found myself a bit disappointed that the upgrade will corrupt my equations. sizeof( quint8(0)); // 1 byte sizeof(~quint8(0)); // 4 bytes Usually something like this is done for a good reason, but I do not see any reason why a bitwise operator would essentially need to add more bits.
How many bits' address is required for a computer with n bytes of ...
2012年12月10日 · For example, you can store 256 different values in an 8 bit number, so 8 bits can address 256 bytes. 2 10 = 1024, so you need 10 bits to address every byte in a kilobyte. Likewise, you need 20 bits to address every byte in a megabyte, and 30 bits to address every byte in a gigabyte. 2 32 = 4294967296, which is the number of bytes in 4 gigabytes ...