Tact as a unit of measurement
With colleagues, we discuss a ridiculously simple question: what is the clock cycle of the processor? Wikipedia clarifies:
In the very first approximation, the clock frequency characterizes the performance of the subsystem (processor, memory, etc.), that is, the number of operations performed per second.
Two options are discussed:
- changing the value of a bit (one)
- assembly operation (over a set of bits)
Thanks!
4 answers
The work cycle is the work cycle, i.e. the time interval between two adjacent "peaks" of a certain master clock signal. Unfortunately, we can't do without it, because our circuits are digital and we need to record the state of the signals. Physically, the clock cycle relates indirectly to changing bits and executing commands. First, different processor units operate at different frequencies. But if we consider the simplest case, then one command is executed at least in one clock cycle of the executive unit. All sorts commands like multiplication or division can be executed in hundreds of clock cycles. Secondly, the processor communicates with the outside world via buses, for example, the data bus. This bus has a bit depth of, for example, 64 bits. Again, in the simplest case, we can use this bus to transmit a number of information per unit of time equal to the product of the frequency per bit. I.e., one transmission can be made per clock cycle, while all 64 bits are transmitted simultaneously
Once again, I will explain that the "number of clock cycles" is essentially the unit of time measurement. Communication with time via frequency:
If we talk about the clock cycle of the processor-this is
The interval between two clock generator pulses
That's what they taught us at the university. When I developed the calculator on the circuits, the clock was the pulse of the signal.., and I agree with @avp
But if you answer the question Такт как единица измерения these are:
A separate stage (time interval) of a cyclic process
And here it does not matter whether one operation is performed, or a set of operations, changing 1 bit or several bits.
A clock frequency generator (clock pulse generator) generates electrical pulses of a given frequency (usually rectangular in shape) to synchronize various processes in digital computer devices. Clock pulses are often used as a reference frequency-counting their number, you can, for example, measure time intervals. link
GTCH is required for multiple processes of the same processor to run sequentially, first setting the command address to the bus addresses, then after 2 clock cycles reading data from the data bus, after 80 clock cycles performing decoding of the read command, and so on.
The number of clock cycles produced by the generator since the power supply (turning on the computer) is stored in a special counter that can be read.
Rectangular pulse circuit
I think
Assembly operation (over a set of bits)
This is a sequential operation (we consider it in the context of a single-core machine), so we come to the definition that the clock frequency is the number of operations performed per second. Although if the operation on a number of bits is done in 1 clock cycle(for example, multiplication), then the number of bytes in this operation is not taken into account