Controller for DVR alarm out

Help & Support Robot Parts
1

Hi all,

I’ve got a DVR system for security cameras. I’m looking for a USB controller which allows me to sense the alarm out leads. Just as a guess, I figure it’ll work like a switch. When the alarm is active, the switch will probably close for 30 seconds or something like that.

The manual to a similar unit Swann DVR 8500AI

Basically, the device has no alarm to email alert which I plan to add. I figured this would be the simplest way.

I’ve been programming quite a while, so I’m not afraid to be slapped with 10 book/manual references, if they are relevant.

I was looking at the Arduino Diecimila USB Microcontroller Board and thought that might work.

Any advice?

John

2

Hello John, welcome to the RobotShop Forum.

The Alarm outputs are TTL level outputs (0/5V) which are perfect for interfacing with microcontroller inputs such as the Arduino USB.

Simply place a 10K oHm resistor on the line from the alarm output to a digital I/O pin on the Arduino. Mind you, an Analog Input may also work but you might aswell use digital inputs.

The Arduino is easy to program so this should be a quick project. A small C# application can then be created to receive commands from the Arduino via the USB port (logical COM port) and send emails or whatever you wish.

Regards,