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Today we are going to touch on and dig out some old, published articles here on blogElectronica.com from several months ago, nearly two years ago. Do you remember this article from the end of 2009?

http://www.blogelectronica.com/cinterion-eu3/

In this article, I talked about the imminent appearance of the new EU3 Cinterion module highlighting that one of its greatest strengths was that it supported the new 900MHz UMTS band that was approaching. The following is worth remembering from this article:

“From a technical point of view it’s better because it offers a greater coverage and penetration than the current UMTS2100, which is ideal for rural coverage and even coverage in cities where the greater the ability to penetrate, the better the coverage in buildings.

It’s obvious from an economic point of view.  One reason is that in order to have a greater scope to cover a specific area, you need to install less base stations with UMTS900 than UMTS2100. Another reason is that the current GSM stations are still valid and they only require small, inexpensive adaptations unlike the UMT2100.

I only have one more tip for those of you who are going to start a new project today with GSM/GPRS modules and who are looking into the future and who are evaluating modules from different manufacturers. The tip is that you read the announcement in the news about the new EU3 module published on Cinterion’s website. Pay special attention to this title, “Cinterion Announces First UMTS Module to Support Seamless 3G Transition for Existing GPRS/EDGE Designs”.

A little later in the article from May 2010:

http://www.blogelectronica.com/banda-umts-en-900mhz/

We talked about everything more deeply on a technical level with the 3G 900MHz (it is recommended reading). One thing to note from this article, as many people asked and will ask this question, is that both in the text as well as in reader’s comments is the clarification that current GSM/GPRS technology (at 900MHz) will coexist with the new 900MHz UMTS.

Finally 10 months ago I posted an article on the EU3 module’s TCP/IP stack:

http://www.blogelectronica.com/eu3-modem-hsdpa-usb-rs232/

Note the last paragraph where it says:

“Finally here is a detail worth noting. The same B2B connector and (nearly) the same pinout as in the TC63i have been used with the EU3 Cinterion module. Therefore, whoever is designing a board to use with the TC63i, I recommend you to take a look at an application note called EU3_e-migration (which is part of the EU3 documentation) as it shows small differences to consider when moving from the TC63i to the EU3. Or rather, this document allows us to design a board in a way that we can use the TC63i or EU3 interchangeably, with obvious advantages that we can use in the future. If some of you are undecided whether to use a MC55i or a TC63i with a new design (I see this happen often), you should consider the compatibility with the EU3. At least it helped me to decide.”

Those who betted on the new EU3 Cinterion module or made a design with a TC63i and considered the application notes to make a compatible circuit like we talked about here, they can start to reap the benefits from the 9^th of September (because it’s an implementation process that will last a couple of years).

Here you have more information of the implementation of the new 900MHz UMTS:

http://bandaancha.eu/articulo/8031/3g-mejorara-drasticamente-cobertura-partir-9-septiembre

Well, I hope that this article has been interesting for some of you and satisfying for others who have made the right choice. I will now continue working on the new version of the MTXTunnel v6.0 manual which will be out soon.

Today I am going to present an interesting device from the company Multitech. I will be making use of a document written by my colleague Jesús Santos, whom I thank. I will be talking about the MultiConnect AW MT200A2W.

Very good. What is it?

Well, imagine you have a device that uses an analog modem to communicate (one external or internal inside the device itself) or simply imagine that you have a switchboard or a traditional fax machine where data is managed (not voice data).

Now imagine that you want to install this device and for whatever reason but it turns out that you don’t have a free telephone line to connect to or simply imagine that you don’t want to use a new analog line or that the telephone cable installation could be expensive.

For that you need this device. It’s an analog line emulator for GSM (for data). This means that instead of plugging the analog modem into the conventional telephone socket, you can connect it to this Multitech device’s RJ11 opening. Thanks to its internal SLIC (that we’ve already talked about), it’s a module that emulates a telephone line.

How easy! Does that mean that the MT200A2W collects data from the SLIC coming from my analog modem and it sends the data directly through its internal GSM modem?

No, you are missing something. The MT200A2W also has an internal analog modem socket that communicates with your analog modem through SLIC. Therefore sending analog signals directly via GSM through the audio channel wouldn’t work due to the damage that these signals would suffer in the GSM network. Then the data is routed through the internal GSM modem in the Multitech device.

This means [your analog modem] — [SLIC--- analog modem socket --- microprocessor --- GSM modem]

Can I not do this with the classic FCT, wireless local loop or gateway that my GSM operator gives me?

No, it won’t work. The devices that you are talking about are designed to connect to analog telephones and to route calls when we phone a mobile telephone, but only to route VOICE calls, not DATA calls. Data calls will NOT work properly with a FCT.

That’s interesting. I understand that you’re talking about the MT200A2W but I see that in reality that there are various models.

Yes, there are two. The MT200A2W, a device designed more for indoor use which has plastic housing and is nicer aesthetically. On the other hand we have the MT100A2W which has aluminium housing, a voltage range, extended temperature range, RS232 port etc. This means it’s more industrial. An important thing to consider when choosing the model is that the MT200A2W model is only able to make calls (calls made by your analog modems) and the MT100A2W is able to both make and receive data calls.

Well that’s all for today. I hope you all had a good holiday. As for me, I had a great 3 weeks holiday. I spent most of the time in Huesca, a great place to relax, to do adventure sports, to eat well as well as always having nice people everywhere. In short, my family and I had a lovely holiday.

Best wishes.

If you have ever developed devices within the category that we might call “on-board” (devices for cars, buses, trains etc.). Did you know that one of the biggest and most common problems is related to vibrations?

The problem is accentuated especially if the device that we are designing is going to use USB peripherals, for example if you are connecting a memory pen drive, a USB video camera, GPRS, 3G modem etc. From short to medium term, if vibrations are intense, it’s easy to see how USB devices don’t work as they fall out. A few developers even use silicone in order to attach USB connectors and avoid this problem.

You already know that I don’t usually talk about connectors but I like talking about some from time to time when they stand out for a special reason. Therefore I am going to post about one of those connectors that make an engineer’s life easier. Here you have a photo of the new connector from the company Amphenol LUSB-A111-00.

If you look, you will see that the USB connector has a tab at the top. The tab tilts as indicated by the arrow, you can lift it up by pressing it with your finger.

When the tab is pulled down, two pins are fixed into the connector’s two anchor holes (any USB device has these). This way no matter how strong it is, no vibration will disconnect the USB device from our connector. It needs a force of 10Kg to release it, so you can only disconnect it if you do it intentionally.

So there you have it, another connector to consider in order to avoid typical problems and annoyances that occur when your equipment is installed in strong vibration scenarios.

I hope that it was interesting for some of your projects.

Regards.

Today I am going to post an article that I’m sure will be interesting and curious to many, especially those of you who are regularly working with GSM devices. Last Thursday, I finally brought a little gadget home that I had bought just a few weeks ago. Nobody has anything bad to say about it, so I wanted to be able to test and compare its ability to Cinterion modems as until now it had not been possible to test it and I had to believe in Jamming detection.

I have based my tests on the official Cinterion application note called “AN_45_Jamming_Detection.pdf”. Here you have all of the documentation on that subject, I2m going to focus on the practical part. As for the modem, I have used a Matrix MTX65i that has a TC65i inside, however I could have used another MTX or Cinterion model and it would have made no difference.

Well yes ok. But what is Jamming detection?

Well to put it simply it is the modem’s ability to detect an intentional interference in communication channels that block them.

You might think that it doesn’t matter and certainly in the vast majority of GSM application this is true, but in safety-related applications (alarms etc.), it’s quite important (or it should be).

Let’s take an example. A house or a car has a typical GSM alarm. If the alarm goes off it must communicate this to a central office of GSM alarm receivers. But, what happens if some thugs use a GSM inhibitor? Could the GSM alarm communicate with the central office? Will the alarm at least be capable to detect interference with a GSM inhibitor and act accordingly?

Obviously, no device (no mobile, GSM/3G module etc.) would be capable of making a GSM communication with a powerful enough GSM inhibitor present. But yes, some devices have (al least) the ability to detect interference from a GSM inhibitor: Cinterion modules. This ability allows them to act accordingly. This means to say that if a device suspects that there is interference, it can try to communicate while the interference is still weak (it can pre-activate warning sound etc.). In short, it’s always best for an alarm device to know what’s happening than to not know, how it acts in these situations will depend on the ability and imagination of whoever developed the alarm.

How to operate Jamming Detection in Cinterion modules:

As I said before, all of the documentation is in Cinterion’s applications 45 note. Basically and quickly summarized, it describes the activation of the communication link’s stability indicator “Ista”, for example with:

AT^SIND=”lsta”,1,5

And to activate URCs with:

AT+CMER=2,,,2

As soon as we activate jamming (interference), we will see how the modem is going to indicate the situation through URCs (sending messages through your serial port). First of all it will send messages like this:

+CIEV: “lsta”, , ,

This indicates that there are errors in the communication link. “lstaEdv” (which is a countdown timer) which will quickly decrease to “0″. Hmm… the suspicion begins…

After this URC, the modem will return another type of message:

+CIEV: “lsta”, , , , , ,

This URC already indicates network coverage loss. According to Cinterion documentation, when you get a URC with “IstaNo” = 40, a low “Istavar” (lower than 10) and “IstaMean” > 40, this is a clear indication of jamming.

As everyone always understands better with pictures, here you have a video which is even better. (If you have received the article via email you will probably have to watch it on (www.blogelectronica.com).

I hope that you found it interesting. Bye 

Today we will see how to make a simple Bluetooth hands-free. In this article I won’t into the audio part, I will focus on the display part of the device i.e. when we engage in a call on our mobile, we can show the caller’s number on an external display which is connected via Bluetooth to the mobile. If we the telephone number is associated with someone in our contacts list in our mobile phone, it also shows us the name of this person.

To do this we need to use a Bluegiga Bluetooth module that has iWrap v4 firmware which makes life a lot easier by running the application quickly and effectively.  Truthfully for what I am going to do we could use any of the WT12, WT11, WT41 or WT32 modules. Even if you later want audio, it will work with any of these modules. I would choose the WT32 which is based on CSR‘s BlueCore5 as it is more suitable for multimedia applications (audio stereo).

So let’s assume that our “Bluetooth incoming call indicator” mainly relies on a single microphone (with 2 UARTs), a display and a Bluegiga WT12 Bluetooth module. Both the display and the WT12 have to be connected to the micro via a UART.

WT12 Configuration

The first thing to do is configure the WT12 Bluetooth module from our microphone. To do this we send the following commands to the Bluegiga module from the micro’s UART:

SET PROFILE HFP ON
SET PROFILE PBAP ON
RESET

With this we activate the Bluetooth HFP (Hands Free Profile) and the PBAP (Phone Book Access Profile– in order to control the contacts list) in the WT12 module. You only need to do this once, once it’s done it stays in the WT12’s non-volatile memory.

Bluetooth Association/ Connection 

Now we are going to connect the Bluetooth module with our mobile phone. Normally you would get your mobile phone and search for the WT12 module in the Bluetooth section and press “connect”. I’ve tried it and this works but I would like to do the reverse, I would like to select my mobile phone in my Bluetooth display and make a connection from the Bluetooth display to my mobile phone.

In order to do this, the following command is sent from the micro to the WT12 module:

HFP 0 RING
HFP 0 CALLERID “681319891″ “” 81
HFP 0 RING
HFP 0 CALLERID “681319891″ “” 81

Today I am going to post a short video about  Multitech routers.

Personally I find these routers (any version: GPRS, HSDPA) very attractive in both performance and robustness as well as being good value for money.  It’s rare, very rare, that a Multitech router malfunctions. In fact I don’t remember anyone returning the product for this reason, as I say they are extremely robust. But it’s not rare for users to have some trouble when using DNAT for port mapping (this is the only thing I don’t like about these devices). It’s not that it doesn’t work as the DNAT works amazingly, it’s the fact that the way of doing it is a little different from what you could be accustomed to when using other types of routers.

Well there you go, here’s a short video that shows you how to make a DNAT.

A month ago I posted about Coronis telemetry devices. We saw that they have IP68 devices that can read remotely via radio frequency (on the 868MHz band), digital inputs, 4-20mA or 0-10V analog inputs and temperatures/meters for water/gas/electricity. A lot longer ago, I also posted a video about the MTX-Industrial modem which you can optionally order with a Zigbee, Bluetooth or Coronis communications card.

So taking advantage of all of this, I have included an additional, interesting feature to the new MTXTunnelv5.6 (which is an application that as many of you know can be requested in any programmable MTX terminal). I have added a GPRS-Coronis communications gateway.

What do you use a GPRS-Coronis gateway for?

Let’s take an example. Imagine that you have a large area (several kilometres squared) with several hundred water meters that you want to read every day. A water meter quite simply generates a pulse (dry contact) for every X litres of water that flows through it. Therefore we will physically connect a Waveflow to each water meter. The purpose of each Waveflow is to count pulses that are generated by the water meter that it’s associated with i.e. said simply each Waveflow will know about the water that has flown through the meter at all times.

Obviously to read meters we could go to wherever they are every day with a PC + Waveport, but it would probably be better to take a reading from your own office as it’s warm in winter and cool in summer and you also avoid travel costs.  This is where you will find the new GPRS-Coronis gateway useful. Let’s look at this explanatory graph:

As you can see the communications hub is an MTX-Industrial (with optional internal Wavecard) + MTXTunnelv5.6.

Very good and how do I read the data from meters from my office?

Among all of its features, you can use Telnet with MTXTunnel. When connecting to MTXTunnel from your office via Telnet you can send AT commands (e.g. switch a relay remotely), read a digital or analog input, read GSM coverage etc. So I’ve added two simple AT commands called AT^MTXTUNNEL=SETWAVENIS,tramawavenis and AT^MTXTUNNEL=GETWAVENIS. With these two AT commands you can directly send Wavenis frames to the MTX-Industrial’s internal Wavecard via Telnet. This will allow you to read and connect to Waveflow meters.

Yes the MTXTunnelv5.6′s new feature doesn’t get rid of the fact that you have to take a look at the Wavenis protocol manual, but it can save a lot of work. For example if I want to communicate with a remote Waveflow I only have to do something like this:

This means that with “AT^MTXTUNNEL=SETWAVENIS”, we send the “frame in question” to a Waveflow and with “AT^MTXTUNNEL=GETWAVENIS” we get the response received from Waveflow. It’s as simple as that. The same goes for being used with any Coronis device, i.e. to monitor temperatures (wavetherm), distributed digital inputs/outputs etc. You have more information in the manual and of course if you have any doubts you can tell me on the blog or via email jose@blogelectronica / jgallego@matrix.es

Normally I don’t talk about connectors in my blog, but the other day in the office (you already know that I work at Matrix) I attended an internal presentation about a new brand of connectors. Something caught my attention and I am posting about it on here today. Knowing that there are already lots of people that read this blog I am sure that more than one of you will be interested.

I will talk about an antenna connector. First of all let’s look at some photos and then I will explain them:

As you can see in the photos, it’s a special antenna connector that allows you to physically switch between and internal and external antennas. Let’s imagine that we design a GPRS device where we want to regularly use an internal antenna. However as we are used to the GSM world and we don’t want any problems, I want to be prepared to be able to use an external antenna in scenarios where we install the connector in places with very low coverage. We have it easy with this connector. When we don’t physically connect the radio device’s external antenna, this connector will use the internal antenna. But when you connect to an external antenna, the connector physically switches by disconnecting the internal antenna and radio device, therefore it uses the external antenna.

As you can see, it’s a connector that is so simple to use as well as useful.  Available for SMA, RP-SMA and N type connectors.

 Any questions you know where I am! 

A few months ago I presented quite an interesting product called CDP (Cellular Development Platform) from Multitech. Let’s remember that this device is a boxed embedded PC based on a 400MHz ARM9 processor that has a GPRS modem inside, ETH port, RS232 serial port, SD card clot and optional GPS. All is mounted on an open platform based on Linux.

Just to tell you, the newly revised CDP is already available. Now you can have an HSPA internal modem at 7.2Mbps (ideal for video applications as the previous version was only GPRS) as well as something that I missed in the previous version which is an increase in the device’s inputs/outputs (as the previous version had very few). In this version the CDP has a 32-pin connector dedicated to I/Os and in which you can additionally find an SPI bus, I2C, ADC and digital inputs/outputs.

Whoever wants to see the device’s complete description as well as programming examples, the best thing to do is have a look at the website that the manufacturer created exclusively for this product:

http://www.multitech.net/developer/products/cellular-development-platform/

Perhaps we aren’t aware that we are being immersed in day-to-day life but without knowing it, the world is completely changing in leaps and bounds. Every day I see more and more different types of company projects that are trying to find a solution to radio frequency. We want everything to be automated, we want to measure everything, we want everything to be optimized, we want to control everything and we want to do all of this from a distance, without wires and without travel expenses.

Like all changes throughout history, any profound change has pros and cons. The upside of telemetry is obvious as we make considerable savings in personnel and we are able to control everything in real time. The downside is job loss. Any job where the main function is to go to a place to take a measurement or a something simple has its days numbered.

In today’s post I am going to describe some “finished” devices (i.e. boxed and ready to use). Some of them are well known to some of you, they are devices with the French brand Coronis (distributed in Spain by Matrix) e.g. Wavetherm, Waveflow, Wavelog, Wavesense, Waveport, Wavesense, and Wavetalk. As there are lots of devices I will give you a superficial description of them, just to give you an idea so that you don’t get tired of reading and writing. I will write about the devices one-by-one in more detail later.

All Coronis devices that I have just mentioned are radio devices that work in the 868MHz band (ISM band, this means a free band as you don’t have to pay for a license to use it). Apart from Waveport, all of the devices are “finished” in an IP68 box, this means that they are designed to work out in the open. They have an internal battery that allows them to be autonomous for up to ten years, I will discuss this later. These devices stand out for two things: the radio link distance and very low consumption.

Wavetherm:

Device for measuring temperatures. There are several options; you can purchase a Wavetherm that uses a Dallas DS1821 probe or the well-known PT100 and PT1000. It’s a programmable device, it can use logger and it’s possible to set a maximum and minimum temperature threshold which will then send an alarm message.

Waveflow:

Telemetry device for energy, water and gas meters. It basically comprises of a pulse reader e.g. every time X litres of water circulates in a water meter, it opens/closes a dry contact. These pulses are “counted” by the Waveflow and it stores the measurements inside. Waveflows with 2 or 4 inputs are available.

Wavelog:

Basically it’s a device for measuring digital inputs or controlling digital outputs. There are up to 4 digital inputs/outputs available.

Wavesense:

Like Wavelog is for digital signals, Wavesense is in charge of analog signals. There are two versions. On one hand you have Wavesense for 0-10v signals and on the other hand Wavesense reads device’s outputs of 4-20mA.

Very good, I see that Coronis has lots of telemetry devices but how do I read them?

With Waveport.

Waveport is device that is available with two communication interfaces. With a USB port or with a RS232 port.  They are basically the same because whoever uses the USB version will actually have a Virtual COM (using a typical FDTI chip) therefore it works the same way.

Wave port is designed to connect itself to an intelligent device, to a communications hub (a PC or PLC etc.) i.e. something where there is a running program that’s responsible for saying to Waveport “go, tell me Wavetherm’s indicated temperature with the MAC address XXXXXXX”

What is the range of Coronis communication devices?

Well it depends on the type of device. Waveport and Wavetalk devices are available in 25mW and 500mW. The rest of the devices are only available in 25mW. In general terms 25mW Coronis devices can reach up to 1Km as the crow flies and the 500mW devices can reach up to 4Km.

And what happens if the distance is greater than mentioned above?

Well you can use Coronis relays, Wavetalk devices. When communicating with Coronis devices, you can insert up to 3 relays i.e. up to 3 Wavetalk devices. Therefore, when using 500mW devices you could have a radio link range of up to 16Km.

So is it always better to use 500mW devices than 25mW devices or not? 

Not really. They are more expensive, they consume more and unlike 25mW devices they don’t use FHSS (frecuency hopping) and therefore they are less immune to interference. You should use 500mW devices when you need to use them for greater distances.

Above you said that the battery lasts for up to ten years, is that true?

Yes, but it depends a lot on how you use the device and what you want it to do. It’s complicated so if you ever want to know how long your battery would last in a given scenario, tell me the details. To give you an idea, the battery from a Waveflow device that reads meters will last for around ten years if it takes one reading per day.

One reading a day? That’s not much…

Coronis devices (with batteries) are NOT designed for intensive use, at least not using the battery supply. They are devices that are designed to take a few readings over time so that they can spend most of the time in sleep mode. If for example you are looking for a device that does a meter’s telemetry ever 10 seconds, a Waveflow is not for you. You could use it, but it would flatten the battery within a few weeks.

Are the integrated batteries only in the IP68 version? I would like to integrate them like an OEM module in my own circuit so that I could use them with bigger batteries or even use a 220v adapter so that I wouldn’t have to depend on batteries. 

Coronis also have the OEM version of these devices. The limitation is the MOQ (Minimum Order Quantity). This means that if you have a project for 100 or more devices, you could purchase OEM modules. If it’s a small project for a couple of units you can’t get the OEM modules.

Well that’s enough for today. This is a very brief overview of these devices. We haven’t gone into any detail as these devices offer a lot more than what I have mentioned here. All we have today is a description; I will go into detail about Wavenis communication protocol, network architecture and communication hubs etc. in the next post.