Amol's Blog

I have been thinking about some things in the afternoon and I am going to note down about one topic that stood out, microprocessors. This topic is the subject from the past, from the college curriculum.

I have studied parts of the microprocessor book. I have studied electronics. I have seen the books related to microprocessors and I have seen the books involving topics related to transistors, etc.

How it comes together can be thought about. As an engineer who is long out of his college, this might be a good mental exercise.

Basic question is, how does a microprocessor work, with the concept of a microprocessor, transistors, and micro-programming. It can all be put together now, along with some more miscellaneous concepts.

Basically, a microprocessor is a very huge collection of transistors. These transistors can hold/transmit voltage, which gets interpreted as a 1 or a 0 at some place, this is also a concept. How does an instruction get executed? An instruction, loaded and interpreted as a set of 1’s and 0’s itself will be applied as the corresponding voltage(s) to the relevant transistor set, of course, after becoming microcode which can be understood by the microprocessor hardware. This voltage set, when applied to the right set of transistors, gets transmitted to the right final set of transistors, after passing through the gating transistors. It reached the final transistor set/area, which, I think, is, something like, one set/area per microcode instruction. This final set then lights up with the right levels of voltages, transmitting the voltages along microcode circuits made of transistors, an advanced version of adders, etc. which can be found in the college textbooks. The result obviously appears as a voltage set which gets collected as output, and, gets interpreted as a set of 1’s or 0’s, just like the computer engineers describe it, or, like it. This may be how it basically works. And, I think, that, there must a set of transistors, a large one, like in millions, one, for each instruction in microcode. This fits well with the number of transistors found on the modern microprocessor, which is in billions, if we go with the millions number for each microcode, then the number of instructions in the microcode instruction set can be calculated to be in hundreds.

This is my basic guess on the functioning of a microprocessor.