This is a "new" version of something I have had for about 25 years.
The original box/case was an aluminium box and the buttons/switches were drilled in and there.
The new box is a plastic one and a completely different shape.
Alas now it is a bit too late to think "I should have done it differently".
The original box (top view) was nearly square. The new one is more rectangular and it is oriented that I look at the narrower side/end.
The "front" is only just wide enough that the display fits left - right.
Also the Arduino and shield take up 90% of the height.
So there is scaresley any space on the front to put the switches/buttons. Alas the 7 buttons of the shield would be handy, though only one is an absolute must - as I need to press something to turn off the alarm.
On top of that, I need some swithces to control the "mode" of what happens at the alarm time/s.
So I am kind of stuck to "how/where" I am going to put the switches, and what "kind".
Membrane type would be nice as they are low profile and don't need that many holes to be made. They simply stick on.
I am stuck for ideas about the type of buttons to use.
Are these "membrane" buttons available for people like "me"?
I am also going to need help about getting the existing buttons on the PHI-2 shield to an external point so what ever I use, I have a simple point of interconnect.
I'm guessing I read the code and find the pins used by the buttons/assigned to the buttons and get something going from those pins to the connector.
I guess I am a bit stressed with where things are and the final parts to get the project working.
If I were you, I would eliminate the buttons completely (because of the space limitations). I would remotely control the device through either infrared or bluetooth. You very probably already have a TV (or Apple TV) remote control already, and maybe even an Android phone with bluetooth.
Both IR and BT solutions cost about the same as the keypad solution you have in mind. Also, libraries for both are readily available.
I shall investigate the remote idea, but at this stage it is only complicating something which shouldn't be that difficult.
It is only an alarm clock. The 6/7 buttons on the sheild are "accademic" in that they won't be used in normal operations, though I will have to work out the ALARM CANCEL button.
I could make them all analogue and save myself 5 inputs.
I'll do a bit more looking and thinking. I nearly have it working so if I can get it "limping along" it may suffice for now, but I would love to get it to full maturation at some stage.
Why not embed an accelerometer into the system. Then you can cancel the alarm by hitting or shaking the alarm. Be sure to anchor the rest of the components well
There is also the thought that your clock is a person too a and using an accelerometer could leave evidence of your brutality behind in it's little memory ...