As they say, “if you comb gray hair” you will remember what old keyboards were like and the problems they caused due to various factors. The technology has evolved a lot and has solved all the problems in this aspect, focusing everything now on performance and general quality, as well as small innovations, but how did they do it? as a keyboard manages to avoid an effect like ghosting? Let’s see it.
First, a brief introduction to the Ghosting effect to understand how keyboards manage to avoid it entirely in the vast majority of models. The Ghosting on a keyboard It is an effect that produces the non-registration of keystrokes on the keyboard when its matrix reaches a certain number of keys when pressed at the same time. How does a keyboard prevent this?
The Ghosting effect on a keyboard and its solution
If the keyboard as a rule has a limit of keys pressed and we press more, these will not be registered and therefore they are classified as “ghosts”, hence the name of the term. But as in everything, there is a limit for the before and another for the after, where the second is the one that varies.
On most keyboards, you can only press one maximum 6 keys at the same time because each key represents one byte, but the input protocol and HID of a keyboard only supports 8 byte as such. The answer to the two missing bytes comes from the reservation of the modified keycaps for special functions or FN plus the reservation keys as such, specific for specific tasks such as Control, for example.
Therefore, and knowing this, the solution is to launch a technology that does not have these limitations, but how to do it if you have to abide by the same protocols and total records? The answer is easy and ingenious at the same time.
Initiation Protocol and Reporting Protocol
The solution came with NKRO, a technology that increased the number of bytes available for each record up to 64 thanks to joining the HID protocols to add a larger bus with the start and report protocol.
To understand it easily, now each key is scanned independently without having a maximum as such, although there really is, 64, of which two are still saved for the aforementioned tasks. But then, how are we going to be able to press all the keys if there are more than 62 on any modern, normal-format keyboard?
Even more ingenuity here, since to overcome this limitation the keyboards include small ARM processors that what they do is emulate two HID keyboards, dividing its matrix into two well-assigned parts, so that if higher keystrokes are necessary for the reason that In other words, the processor works and emulates two keyboards for the same USB, allowing full keystrokes.
As we can see, these little 32-bit ARM processors Added to the system memory, they make the current small “PC” keyboards that are really powerful given the numerous amounts of options they have today, far beyond RGB systems or keys.
