6 replies to this topic

[alanb]

Hi, For my project I need to let the user enter data. So I need to use a keypad. I saw this http://www.sparkfun.com/products/8871 sealed membrane keypad. Or alternatively this http://www.sparkfun.com/products/8653. My preference would be the first one because the arrow keys etc would be useful. I just am interested if anyone has used either keypad and how easy each is to interface to the N+. There is an arduino forum discussion (http://www.arduino.c...um=1209003950/0) on using the second keypad but I can find nothing yet about using the sealed membrane keypad. Alan

[Fabien Royer]

Hi Alan,

This method works quite effectively and only uses one analog pin on the netduino: http://www.instructa...-Matrix-Keypad/

Cheers,
-Fabien.

[alanb]

Thanks Fabian, Unfortunately I need rather more keys that 0-9 # and * , I want to be able to enter decimal numbers so thats 0-9 and . also to move forwards / backwards in increments on a single button press so thats two more keys < and > also to start and stop moving continuously thats two more keys plus keys to select a couple of operating modes such as selecting the increment etc. So I reckon a minimum of 16 buttons are required. I guess I could use two pads but I would rather have the buttons in one pad. Alan

[Fabien Royer]

Have you considered adding a serial interface to your project?

[alanb]

Fabien, I hadnt thought of that, still fairly new to this hardware stuff. Can you get serially driven keypads quite cheaply? In any case I thoght that if my first preference keypad worked out ok, I would dedicate a processor to it connected to N+ serially. My output screen is serial. Alan

[Fabien Royer]

Oh! You have an N+?
Then all you really have to do is to build a web-based interface that you can access over Ethernet
I only suggested a serial interface because I thought you had a regular netduino or a mini.

[alanb]

Not really, I am building a stand alone stepper controller for my rose engine, which will not be connected to my network except to download some tables. I got the N+ to use the SD card!! and network connection for downloading. But control of the machine is via keypad buttons. Alan