Category Archives: GSM Door Entry

v1.07 Software Release for setting up Diallers and Intercoms

Our software allows you to change your dialler and intercom settings, numbers and messages remotely using the internet.  It requires a small amount of data allowance to be available on your SIM.  A session will use a couple of kB.

v1.07 will work with any firmware release from 5.10 onwards.  We can remotely update your dialler and intercom with the latest firmware if required (you must have at least v5.10 to start with).

The software is available from our Downloads page:

http://www.adventcontrols.co.uk/pages/downloads

Please note currently we do not require installation of the software which is available as a raw EXE file.  If you download this from our website you can trust it.  You may need to click ‘run anyway’ on the Windows security message box.  We will release an installation version over the next few weeks.

May 16 Update Video: Dialler PCBs, Gold Intercom and PC Software

Video Timing

  • New Roller Shutter PCB (2-in 2-out PCB) 0:20s [C4 Webpage ]
  • D4 Analogue Voltage Measurement and 6 input PCB 0:36s [D4 Webpage]
  • D4 PCB also PCB tested in software 3:20s [D4 Webpage]
  • G2 GSM Intercom 0:55s [GSM Intercoms]
  • New A4 PCB 1:55s [2-Input GSM Dialler]
  • PC Control Software 4:40s [PC Software Download]

In the video we mainly demonstrate the PC software.  This connects via the internet to your PCB and allows you to view settings and numbers as well as monitor the system live.  The PC software in on the whole done we’re waiting for our server software to be complete.

PAYG SIM Card Deactivation

When using Pay As You Go (PAYG) SIM cards in equipment such as dialers and gate openers you should be aware that the network may chose to deactivate your SIM card should you not meet the minimum usage requirements.  In the UK the strictest networks require at least a call or text message to be sent once per quarter – Lebara Mobile require 1 call/SMS per 3 28 day calendar months.

For details of the terms and conditions for each network I recommend following this link with an excellent article written on the subject:

http://kenstechtips.com/index.php/payg-inactivity-account-termination-and-credit-expiry

Further details can be found here on the basis for these policies:

https://community.giffgaff.com/t5/Blog/Recycling-mobile-numbers-giffgaff/ba-p/8211666

Our GSM equipment has two SIM card Keep Alive functions which automatically send an SMS or dial a number to keep your SIM card within the terms and conditions of the network.  All products have the Keep Alive Text feature which sends an automated SMS message at user specified intervals to their chosen number.  This is set up as follows:

KAT 07000000000,28.       Sends a keep alive message every 28 days to 07000000000

Dialers and Gate Openers with firmware version 3.18 or later additionally have the ability to dial numbers where a voice call is a requirement.  This is set up using the following command:

KAC 01512834306,80.      Dials 01512834306 every 80 days

Should the call go unanswered it unit will retry 4 times and will then send an SMS to the first master number with the following text ‘KAC@Fail’.  In this case a manual call should be made with the following command:

Dial 01512834306.     …or the number of your choice

Where your network requires a call to be made but your device has firmware prior to F3.18 we recommend setting the Keep Alive Text message to remind you to make a manual call for your required interval using the dial command.  Ensure the call is answered.

What’s new in July

We ended June having brought our new Gold G2 2-Button Intercom into full production and having restocked our old 1-Button internal aerial unit.

GSM Intercom

Advent Controls G2 Intercom

We have a new PCB which will form the basis of all of our dialers and gate/shutter openers going forward.  It features an ultra-low power mode, more inputs and outputs, space for a voice unit and Bluetooth.  The chip on the PCB has a larger program memory (like the hard drive of a PCB) giving us space to add more features.  The power supply design is more rugged too allowing for higher voltages and better surge protection.

B3 PCB

GSM Roller Shutter Controller

We’ve finally given up on the Circuit Switched Data (CSD) system we used for remotely connecting to devices in the field and have revised the software to use the GPRS packet data system.  We chose CSD as it meant your SIM did not require data and there was no need to tell the GSM unit your network’s APN (Access Point Name) e.g. giffgaff.com…  The problem is CSD does not really work at all never mind reliably.  Quectel have dropped support on the new modems we are using so it was time to switch to GPRS.

GSM assembly code

We’ll be using GPRS to dial in in future

There are huge benefits though.  The newer PCBs including our Gold G2 Intercom can have a full firmware update over the internet using GPRS.  We have also added the ability for the dialers and gate openers to send emails whenever activity is detected.  Eventually we will either offer our software to the end user or create a web interface for setup to be done online.

Setup GSM dialers and intercom online

Advent Controls Web Interface Software

New features – feedback definitely welcome!!

  • Dial, SMS and email
  • Bluetooth Setup
  • Low power modes
  • PC interface software
  • Ability to email list of settings and stored numbers
  • 2-In, 2-out PCB due August
  • Keep Alive text to display balance

Michael Beaver, Director

Gold G2 GSM Intercom Door Entry Phone Update

January has proven to be a busy month with many trade and online orders for our ever popular GSM Auto Dialer system (GSM Dialer).  We’ve also taken on a new member of staff, Kelly, to handle orders for this product.  Hopefully for her sake the next couple of weeks will be a little quieter!  It would also allow further progress on our new Gold series of intercoms.

GSM for AndrewWe have been installing the first of our Gold Series GSM Door Phone Intercoms which is the Gold G2 Model.  However they are still in short supply and we’re still working on the firmware.

The early versions have been using the Capacitive Sensing Module on-board the PIC microcontroller.  This has proven highly reliable and accurate in the field however in theory this module is susceptible to electrical interference.

CSM Scope View

CSM Pad Trace

The CSM module generates a frequency dependent on the capacitance applied to the pin of the chip.  However it is possible for the touch pad to pick up high strength electrical noise and start oscillating at the frequency of the noise.  This would be seen as a press even though nobody touched it.  In practice we have not seen this but we also developed an alternative software based decoder which measures the voltage on the touch pad after it has been discharge and charged by the Analogue to Digital Convertor (ADC) sampling capacitor.

CVD Touch Pad Trace

CVD Touch Pad Trace

This technique of measuring the pad charge and then discharge into the same capacitor is known as a Capacitive Voltage Divider (CVD).  This method is very resilient to noise and electrical interference but does require more CPU processing time.  It is likely to be implemented across all of our Gold GSM Intercoms and will soon be behind the touch pads of our G2 unit.  When we have a full keypad version of the intercom available it will be important to use this technique hence it is being developed now.

GSM Call List AT+CLCC Customer Question (it gets a bit technical!)

Hi,

When I use my smartphone, the dialing screen turns green when the number I called answers,​ h​ow that’s accomplished? Do you know if your chipset has the hardware ability to determine when the call is connected, like via the gsm protocol stack?

​That​ can’t catch the automated voice messages from the phone company (like “the ​number you ​are calling ​is unreachable”) but it can eliminate the ringing tone and that would be sufficient.

DSP would be better but as you say it can’t be readily nor easily done.

Regards

GSM Intercom Question Reply

Ringing GSM Phone

[Note: the customer would like us to stop the 400Hz ringing tone from being audible during a call]

Hi <name>,

The network will tell you some things about the call but often (especially when you use a network reseller’s SIM card) it does not give accurate information.

For example, in the UK a company called Lyca resell the O2 network airtime. When using their SIMs the CLCC data in invalid. This is why we had to offer an option to turn off the voicemail divert command. Normally we detect voicemail diversion by noting when the phone does not ring. If the phone is switched off it will dial then instantly connect to the voicemail service which we can see happening from the CLCC command. We see it going to status 2 to 0 and never getting to 3 which is the ringing status. However, Lyca always show transition from 2 to 0 regardless of whether the phone rings or not and never give a status 3 when the phone is ringing. Basically the network notifications are unreliable.

Our intercom (available here) unit has a connection to the microprocessor from the audio circuit so we can digitize the audio and detect frequencies and whether there is audio or not. This is how we implement the SILENCE command functions.

We could switch the volume down to 0 during status 3 on a CLCC request but this may not work with some networks. That would be the easiest way to do what you require. I’ll look into it

Reply from AT+CLCC    NB:  <call state> is of interest here

+CLCC: <idx>,<dir>,<call state>, <mode>,<mpty>,<number>,<type>[,<alpha>] [<CR><LF>]

<Parameter>
Description
<state> 0 Disable CLCC unsolicited indication1 Enable CLCC unsolicited indication
<idx> Integer type, call identification number
<dir> 0 Mobile originated call (MO)1 Mobile terminated call (MT)
<call state> The state of the call0 Active1 Held

2 Dialing (MO call)

3 Alerting (MO call)

4 Incoming (MT call)

5 Waiting (MT call)

6 Released

<mode> Bearer/Teleservice0 Voice Call1 Data

2 Fax

<mpty> Multiparty status0 Call is not part of a multiparty call1 Call is one of multiparty call parties
<number> Phone number in the format specified by <type>. Contains a string of up to 32 characters.
<type> Phone number display format. Type of address octet in integer format (refer to GSM 04.08 [8] subclause 10.5.4.7) 129 Local number

 

 

 

Regards,

 

Michael Beaver