![]() Post moved to new location on September 28, 2017. While the average consumer may not notice these increases, they are greatly appreciated in the fields of numeric computing, scientific analysis, video encoding, and encryption/compression. According to Harry Henderson, in his book titled Encyclopedia of Computer Science and Technology, IBM is believed to have coined the term word processor. This is why so many instruction set extensions (MMX, SSE, etc…) have been created: to process larger amounts of data in less amount of time.Ī larger word length in a processor does not directly increase the performance of the system, but when dealing with larger (or higher precision) values is required, exponential performance gains can be realized. The bottom line: larger word lengths means we can process more data faster in the processor, which is greatly needed as we advance computing technology. You would have many extra clock cycles dedicated to fetching and parsing those wider numbers, whereas those operations go much quicker on a processor that can handle it all in one word.Īlso, while increasing the number of bits in an arithmetic and logic unit (ALU) will increase propagation delays for most operations, this delay is very manageable in today’s processors (or else we couldn’t keep the same clock speeds as our 32-bit processor variants), and is not much use when discussing digital synchronous circuits (since everything is clocked together, if the propagation delay was too long, the processor would just crash – which is also why there are limits to overclocking). If you needed to address past 4GB on 32-bit, you would need to compensate for that kind of like how we added a 64-bit number on our 32-bit machine above. On a 32-bit machine, pointers can address ~4GB of RAM, where they can address over 16.7 million TB on a 64-bit machine. Where I’m going with this has performance implications specifically with pointers. In order to perform word processing, specialized software. However, they also include computational science (the use of algorithmic techniques for modeling scientific data), graphics and visualization, human-computer interaction, databases and information systems, networks, and the social and professional issues that are unique to the practice of computer science. STAA64 However, this takes two again, since we need to store a 64-bit result 32-bits at a time.Īs you can see, even a hardware implementation of a 64-bit addition under a 32-bit processor still takes 7 clock cycles at minimum (and this assumes all memory reads/writes take a single clock cycle). Word Processing refers to the act of using a computer to create, edit, save and print documents. LDDA64 Takes 2 clock cycles, since this number is fetched 32-bits at a time So, let’s assume we have two 64-bit registers (A64 and B64), and have an operation called ADDAB64 which adds A and B, and stores it in A: This is why 64-bit versions of many image/video editing programs outperform their 32-bit counterparts.īack to high-precision operations, even if you add the ability to a 32-bit processor to add two 64-bit numbers in a single clock cycle, you still need more than one clock cycle to fetch those numbers from RAM, since the word length (again) is often the fundamental size of memory operations. Likewise, if we had to make a copy of some data in memory, assuming everything else is constant, we could copy twice as many bits per cycle on a 64-bit versus 32-bit machine. This is the real key to 64-bit and 128-bit processors: they allow us to handle larger numbers of bits in a single operation. Going through my made-up assembly syntax, you can easily see how higher-precision operations can take an exponentially longer time on a lower word length machine. The 6-bit encoding allowed the mapping of most of the punctuation but left no room for lowercase letters.CLRA I'm assuming the condition flags are not modified by this.īRNO CMPS Branch to CMPS if there was no overflow.ĪDDA #1 If there was overflow, compensate the value of A. This is because, at the time, most machines used words whose length was a multiple of 6 bits see the next section for clarification. ![]() In the 1980s, 5-bit bytes started being replaced by 6-bit bytes. Even though it was later dropped in favor of longer bytes, the 5-bit byte remained in use until the 1980s for encoding other character sets, and in particular Arabic and Farsi: ![]() In that encoding, a byte comprises 5 bits and allows the mapping of all uppercase Latin letters plus some punctuation. One of the first encoding for characters into bits derived from the International Teleprinter Code of the IX century. The byte today consists of 8 bits, but this hasn’t always been the case. Instead, they operate on collections of bits that take the name of bytes, and that are the smallest units of information that they can address in the memory. Modern processors don’t however perform direct operations on them, not even bitwise logic. The smallest unit of digital information is the binary bit.
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