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author: merlin
author_rank: Newbie
timestamp: November 30, 2017, 04:40:39 pm
content: hi there i know there is hundreds of ardunio based alarm systems but non of there are what i am wanting and the branded systems that have what i want are too expensivewhat i want isi would like at lest 24 zones all wireda tamper circuitto be able to use off the shelf pirs and door contactsto be able to have a lcd based control pada gsm moduel to send texts when a zone is triggeredto have multiple pins / tagsto have different programs (have some zones active and some not, a full set etc)to have a sirenwhat i would likerfid reader to set and unsetwork with a mag lock to lock the door when set and unlock whan unsetto name each zonea key switch to arm but not dissarmany help is appreciated

author: rstofer
author_rank: Super Contributor
timestamp: November 30, 2017, 06:10:47 pm
content: You any good with C? You're probably looking at several thousand lines of code.You will probably want to store the configuration data (zone lists, names, codes, etc) in an EEPROM separate from the codespace of the uC. You could actually do this with a SD card. This way you could do the configuration on a PC, write the SD card and plug it into the alarm. The alarm system would read the configuration and do whatever.I would start with something much larger than an Arduino although it could be made to work. I would prefer to work inside a veritable 'dumpster' than be constrained in code size right out of the gate.You want a lot of IO and there are chips known as IO Expanders that allow you to connect MANY lines to a very few pins on the uC.Alarm loops are usually 'supervised' and there is usually a termination resistor at the end of the loop. The idea is to pass a current through the loop and measure it. If the loop is open, the current will be controlled by the End-Of-Line (EOL) resistor. If the loop is closed, the current will be controlled by the alarm circuitry. The idea is to prevent the line from being cut or shorted without detection. You will need to come up with a way to do this. Or you can choose to skip it...Here's a description of the requirements but I haven't found a suitable circuit.http://www.imsasafety.org/journal/mj09/21.pdf

author: merlin
author_rank: Newbie
timestamp: November 30, 2017, 06:18:19 pm
content: yes i am ok usinf c and i was saying i know there is a lot out there using ardunio and i was looking for another uc to do this and thank you for all the info

author: jc101
author_rank: Frequent Contributor
timestamp: November 30, 2017, 07:06:21 pm
content: Something like one of these will do as a panel and keyprox keypad...https://www.ebay.co.uk/itm/Honeywell-Galaxy-G2-44-Control-Panel-Smart-PSU-RIO-RKP-Brand-New-Boxed/222735265903?hash=item33dc0e706f:g:ubIAAOSwj99aEhwj..although may need some IO expanders and additional PSU's dotted around. These also support standard fuil, part, and night set but also can have groups defined sort of creating multiple logical alarms within a main system. They work with off the shelf PIRs and the like. Been around for years so all sorts of programming help out there.The GSM gateway can be expensive, but internally there are relays for system triggered etc. so was to hook up external dialler or rolls your own.You can build something from scratch, kind of depends on your timescale, and how much work you want to take on.

author: NivagSwerdna
author_rank: Super Contributor
timestamp: November 30, 2017, 07:29:10 pm
content: IMHOTexecom Premier Elite 24Around £200 for some starter bitsYou can interface to that and get zone alerts etc. even when not set.

author: merlin
author_rank: Newbie
timestamp: November 30, 2017, 07:58:14 pm
content: hi there jc101 thank you for your sujestion and my time scale well i dont have one this was just some thing i had an idea to do

author: merlin
author_rank: Newbie
timestamp: November 30, 2017, 08:03:54 pm
content: hi there NivagSwerdna i would be intrested in something like the but a bit price for me hens whay i would like to build my own

author: rstofer
author_rank: Super Contributor
timestamp: November 30, 2017, 11:48:52 pm
content: An easy way to build this thing is with a Raspberry PI and a touch screen display:https://www.sparkfun.com/products/13733https://www.sparkfun.com/products/13825https://www.adafruit.com/product/1946https://learn.adafruit.com/adafruit-fona-mini-gsm-gprs-cellular-phone-modulehttps://www.sparkfun.com/products/13840With this approach, the entire project devolves into nothing more than a Linux application. You have access to all the libraries, the UI can be based on Qt and you can iterate on software as much as you want. You have IO pins available to talk to IO Expanders. Python examples shipped with the distro will show you how to communicate with the IO pins.A touch screen is much more cool than a simple 4x20 LCD with a keypad. OTOH, writing the UI with, I assume, a tabbed display (tabs to select functions) will take some work. Qt has a tab widget:https://stackoverflow.com/questions/16704896/qt-how-to-build-a-multi-tab-windowThis just keeps getting better and better!

author: merlin
author_rank: Newbie
timestamp: December 01, 2017, 12:12:27 am
content: hi there rstofer this looks intresting and looks quite easy to do

author: rstofer
author_rank: Super Contributor
timestamp: December 01, 2017, 03:55:56 am
content: At first I thought your list of features would require endless coding for a bare metal CPU but using the Raspberry Pi means that all of the libraries are already done. I don't mean to minimize what remains but a huge percentage of the code is done and known to work.Google shows lots of information re: Qt on the Raspberry PI and, of course, the PI can be used as its own development platform.

author: C
author_rank: Super Contributor
timestamp: December 01, 2017, 03:55:48 pm
content: Think about what rstofer is suggestinga Raspberry PI and a touch screen display:One a Raspberry PI can talk to more.You could have many touch screen interfaces in system.While One Raspberry PI is probably enough you could have one checking the other for proper operation.You could use connection between Raspberry PI(s) to reduce some wire.And you might want to use some OneWire devices. With OneWire each device has a unique serial number, so instead of checking for resistor at end of chain check for a onewire device, a DS18B20 at end of security wires for example.

author: rstofer
author_rank: Super Contributor
timestamp: December 01, 2017, 05:01:10 pm
content: It is pretty normal to want more than one panel. Depending on the house, a panel at the door from the garage, a panel at the front door, a panel in the master bedroom and so on.Is there one master Pi that runs the show and several slave panels that communicate over a very closed network? The Pi has a full networking stack so why not?If the system is being networked, does it make sense to put remote PIs closer to the contacts (zones)? One downside is the need for power at each PI location unless Power Over Ethernet can be made to work. And it can...https://www.pi-supply.com/product/pi-poe-switch-hat-power-over-ethernet-for-raspberry-pi/