I know that processors perform the tasks in binary. If I give an instruction to the computer, for instance, I have pressed letter "A", which is denoted as 01000001 in binary. How does a transistor perform that task?, more precisely, does a processor use 8 transistors to process this 8 bit of instructions or does a single transistor change its state 8 times to process this 8 bits of instruction? (It might be a very basic question, but I am not a computer expert)
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\$\begingroup\$ "does a processor use 8 transistors to process this 8 bit of instructions" No, it uses a few million CMOS transistors all in paralel to process your instruction. \$\endgroup\$– OldfartSep 12, 2019 at 6:15
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1\$\begingroup\$ I suggest that you read some books about digital and logic circuits, many of these explain how transistors are used to make logic gates and how those logic gates can then process binary data. You trying to step from a single transistor to how a byte is processed is just too much to take in one step. \$\endgroup\$– BimpelrekkieSep 12, 2019 at 6:21
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\$\begingroup\$ Look up a basic NMOS NOT gate. The output turns off when the input is on and the output turns on when the input is off. If you connect several together, the output will turn off when any input is on. And from there you can build a comput \$\endgroup\$– user253751Sep 12, 2019 at 6:42
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\$\begingroup\$ Welcome to the site. The answer to your question is actually an entire subject in itself and pure teaching is not what this site is for, I'm afraid. Here is for solving problems on electronic design. There's plenty of text already written on the subject, though, so plenty for you to find and learn from. Try searching the internet for 'digital logic circuitry basics tutorial' or suchlike. Good luck with your learning and I hope you enjoy the discovery. \$\endgroup\$– TonyMSep 12, 2019 at 6:59
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3\$\begingroup\$ @Oldfart - 8 bit CPUs are much simplier then "few million CMOS". 6502 for example has 4237 transistors. \$\endgroup\$– ufokSep 12, 2019 at 7:15
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2 Answers
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It’s rare for a single transistor to perform any binary logic function (except for very local logic inversion). Usually circuits made from multiple transistors are used to create logic gates, and multiple gates and/or state registers are used to create higher level functions for serial or parallel processing of multi-bit binary operands, and thousands to billions of gates and transistor memory are used to make CPUs or processors.
Also, transistors don’t really work directly with binary digital abstractions, but with varying voltage and/or current levels. However, certain reliably obtainable voltage level ranges, in and out of gate circuits usually built with multiple transistors, are defined as binary logic levels for the purposes of digital design.
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Look for NAND gate, for example in wikipedia: https://en.wikipedia.org/wiki/NAND_gate You will see that this gate is composed from 2-4 transistors. Having NAND gate you can build other logic gates and components. Have fun building whole computer on brilliant page: http://nandgame.com
