I don't understand how a clock and input must work together to accomplish the output. For example PS/2 Keyboard , has a CLK at a frequency lets say 50MHZ , now when you press a key a input goes High. But how does the input and CLK Synchronize together . I hope you understand my question. Thanks.
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the clk has a frequency of 50MHz, this means the clock oscillates 50 million times per second(goes from posedge to negedge).
Since the clk is going os fast, you press a key and the input goes high. Depending on how you create your design, you can either let the system know it either the rising(positive edge) or falling(negative edge) of the clock to make your design do stuff.
TL;DR: If the input is high and the clock changes(0 to 1 OR 1 to 0), do something
Since the clk is going os fast, you press a key and the input goes high. Depending on how you create your design, you can either let the system know it either the rising(positive edge) or falling(negative edge) of the clock to make your design do stuff.
TL;DR: If the input is high and the clock changes(0 to 1 OR 1 to 0), do something
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The clock signal on a PS/2 keyboard or Bus Mouse interface is not a processor clock.
It is a clock that is used with the data line to send data from the PC to the KBD and from the KBD to the PC. It is what is called a SYNCHRONOUS interface because the changes in the data line are synchronized with changes in the clock line. As the two signals are shared for sending data in both directions it is also termed a HALF-DUPLEX interface as only one end can send at a time. This clock is at a much lower frequency and is often intermittent with pauses and may even change in frequency over some specified range around 10 to 16 kHz in a PS/2 keyboard interface.
A processor clock is used to keep the internal functions of whatever micro controller working and may be 1 to 20 MHz typically inside a keyboard or mouse and 50 to 1200 MHz in a PC or other computer that the keyboard is attached to. This clock is not directly synchronized to the communications clock but indirectly does generate it at some level.
It is a clock that is used with the data line to send data from the PC to the KBD and from the KBD to the PC. It is what is called a SYNCHRONOUS interface because the changes in the data line are synchronized with changes in the clock line. As the two signals are shared for sending data in both directions it is also termed a HALF-DUPLEX interface as only one end can send at a time. This clock is at a much lower frequency and is often intermittent with pauses and may even change in frequency over some specified range around 10 to 16 kHz in a PS/2 keyboard interface.
A processor clock is used to keep the internal functions of whatever micro controller working and may be 1 to 20 MHz typically inside a keyboard or mouse and 50 to 1200 MHz in a PC or other computer that the keyboard is attached to. This clock is not directly synchronized to the communications clock but indirectly does generate it at some level.