Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
It looks like one graph is obscured a bit, but you can figure it out.
In one of the modes, there is basically 8 buttons connected to pin 9.
In the other mode it's able to deal with a Keypad without much intervention. A key in a typical keypad, connects a row and a column together. So, a 4 x 4 keypad doesn;t require 16 ports. It only requires 8.
The processor is constantly scanning either the rows and and looking for colum transitions or vice versa. A Row, column pair is mapped to each button.
It looks like in the button mode, it's one port per button.
The chip probably enables the pullups correctly.
This **broken link removed** might give you a better idea of what's going on.
user interface, your choice; e,g. **broken link removed** or **broken link removed** or **broken link removed**
Here: **broken link removed** would be a better example using a graphic module
The buttons don't have to be layed out in a matrix, but typically a lot of interfaces use buttons along the edge. Just look at some ATM's where buttons along the left and right edges were used to select functions.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.