Why does my computer not recognize multiple keystrokes simultaneously?

Question

I'm using garageband's musical typing feature, and am playing three finger chords on the "keyboard". However, when i use the sustain (the TAB key) certain three-finger chords don't play in entirety, as though the computer doesn't recognize that i'm even pressing the keys on the keyboard. The particular combination that is malfunctioning is TAB+S+F+H. I can press TAB+S and it will play the one note designated by the S key, but it will not recognize the F or H if i press them also, OR I can press TAB+F+H and it will recognize both of them together, but won't recognize S if i also press it.

I am baffled, as it's one of just a few combinations that don't work. Any insight? Thanks.

Answer 1

Everything from the design of the keyboard to the drivers can affect the number of keys that will register.



Basically a keyboard is just a bunch of switches. The type of switch might be a mechanical switch to a capacitance type of switch. In both cases, the conductors to all the switches are usually arranged in a grid or matrix. Rows and columns are scanned for key presses and these are translated into numeric values for the computer. By the time they get to a program, they are usually in the form of an extended ASCII set.



In the case of multiple key presses, the problem you are having is caused by conflicts in the switch matrix. It is usually easier to demonstrate on some calculators which usually have a very straight grid pattern but the result is the same. Certain key combinations on a keyboard at intersecting grid locations will cause other letters to be detected depending on how the grid is arranged. In other cases, multiple key presses will only register as a single key depending on which is the first one to be detected from the grid.



You can try other keyboards, but I suspect that the only real answer would be a musical keyboard interface. Even some of the cheaper music keyboards have problems with chords and will not allow multiple keys to be pressed to get a chord.



The best solution is to move to a real musical keyboard that will play chords and allow multiple keys to be pressed. If you want computer control, then you'll need to also look for a computer interface.



Shadow Wolf

Answer 2

It's because many keyboards have a 'limit' to how many keys can be registered at once, and certain combinations are sometimes excepted. Basically, it's the keyboard bios or driver that's doing it, and you can't fix it. Only suggestion I'd have is to look for a gaming keyboard (a bit extreme, but they usually allow many key presses for different uses).

Answer 3

This is a hardware issue, specifically with your keyboard, and how the keys are mapped within the electronic circuitry.

They are made like this to reduce electronic complexity and thus the price of your keyboard.



If you wish to solve the problem, you could look into buying a more upmarket (gamer) keyboard, such as the microsoft sdewinder, though you may find the problem has not been entirely removed.

Answer 4

3 hours