The phrase "a key is pressed" is correct and usable in written English.
It can be used in contexts related to computing, keyboard usage, or any situation where a key on a keyboard or device is activated.
Example: "When a key is pressed, the corresponding character appears on the screen."
Alternatives: "a key is activated" or "a key is struck."
When a key is pressed, a unique make code for that key is sent to the computer.
When a key is pressed, the corresponding metal string presses down onto the wheel, creating a sound similar to a cello.
When a key is pressed, it hits a specific area of the overall membrane and sends the signal to the computer indicating which key was pushed.
When a key is pressed, any additional keys pressed while the window is open are considered part of the combination, while keys pressed after the window is closed are considered a new combination (with a new concurrency window).
Mr. Zylkin says he starts with a typewriter that has been refurbished by a retired Remington salesman, then wires it with a sensor board that recognizes when a key is pressed.
The other was a software program that gathers miscellaneous scraps of data on a computer (such as the precise time that a key is pressed), mixes them together, and extracts random numbers from the pool.
had been used instead then the location would be recorded whenever a key was pressed instead (the Escape key is not considered a key press in this context; it exits the pick call instead).
It made use of a sheet of plastic, on which the keys were printed, overlaying a metallic circuit that registered when a key was pressed.
When a key was pressed, the corresponding typebar would swing upwards, causing the print head to strike at the center of the ring.
The stimulus remained filled in until a key was pressed.
The moment a key was pressed, the fixation point reappeared to introduce the next sound pair.
