I want to detect the presence, or absence, of a sustained 12 V signal.
To protect the Arduino board from beginner-mistakes, I want to use an I²C- or SPI-based shield rather than a voltage divider. That way I’ll burn the shield, rather than the board, when I mess up.
Experience = Minimal
I’m completely new to Arduino. Only done a little programming (entry level Python). I’m familliar with analogue circuits, breadboarding etc. I need help picking a good shield for my project. Could you dudes point me in the right direction?
Currently moving into a new student apartment. A few days ago, a group of kids were sneaking around the area where I’m moving in, checking out windows & taking pictures. I live on the ground floor, so my place is pretty vulnerable. I have blinds & locks, sure, but any window can be opened with a rock.
But I’m not securing a bank vault from the Joker… All I need is something that goes WEE-OOO-WEE-OOO to scare them off if they try something. I have a bunch of sensors from an old alarm system. Sensors work fine, but the alarm central doesn’t work.
Input from each sensor comes in the form of a DC signal.
12 V, <5 µA = No detection
12 V, 5 mA = Detection
A votlage divider would be a simple solution, but let’s be honest: As a beginner, I’m more than likely to burn something. With an I²C- or SPI-based shield between the sensor and the Arduino, then the first thing I burn will probably be the shield.
I only need to get a yes/no indication for sustained voltage.
Do you guys have any suggestions or advice on what type of shield to look for?
Perpherals: 10 sensors, 1 keypad, 1 LCD (status panel).
Siren controlled via 12 V relay.
Board: ATMEGA2560 R3
I’m packing to move. Will check in periodically, but may be slow to respond. Apologies for that.