Telemetry, where to start?

[amerdsp]

Greetings,
I am just starting to learn about this. I am in the midst of a
microcontroller project that I would like to have telemetry
capabilities.
I do not know much about telemetry and what choices/options are
avaialable.
The device would be used across town and I would like it to be able
to send data back to me. It would also be nice if I can probe it to
report some data as well.

Any leads about this? Where do I start looking? Any links, books
reference?

If this is the wrong newsgroup, please let me know.

Thank you for your time and help.

Best,

A

 

[Rich Grise]

Greetings,
I am just starting to learn about this. I am in the midst of a
microcontroller project that I would like to have telemetry
capabilities.
I do not know much about telemetry and what choices/options are
avaialable.
The device would be used across town and I would like it to be able
to send data back to me. It would also be nice if I can probe it to
report some data as well.

Any leads about this? Where do I start looking? Any links, books
reference?

You might try here:
http://www.google.com/search?q=telemetry

Good Luck!
Rich

 

[Anthony Fremont]

Greetings,
I am just starting to learn about this. I am in the midst of a
microcontroller project that I would like to have telemetry
capabilities.
I do not know much about telemetry and what choices/options are
avaialable.

A whole bunch. Go to www.sparkfun.com and take a look at all the neat
stuff you can get. Communications distance is a major deciding factor.

The device would be used across town and I would like it to be able

That narrows things down nicely. ;-)

to send data back to me. It would also be nice if I can probe it to
report some data as well.

Any leads about this? Where do I start looking? Any links, books
reference?

I'm thinking that GSM cellular may be something you could use. If you
already have a cellular phone that uses a SIM card, then you're half way
there. Check this out:
http://www.sparkfun.com/commerce/product_info.php?products_id=278
If you can do python, then you will really like this for only ten
dollars more:
http://www.sparkfun.com/commerce/product_info.php?products_id=279

Look for information on M2M (machine-to-machine) communications.

 

[Chris Hills]

A whole bunch. Go to www.sparkfun.com and take a look at all the neat
stuff you can get. Communications distance is a major deciding factor.


That narrows things down nicely. ;-)

Which town?

What you can safely do in some towns gets you arrested in others and
bombed in others.

I'm thinking that GSM cellular may be something you could use.

Maybe... it depends on networks and which system is used in your
location and the one you want to use the system in.

 

[amerdsp]

I am sorry I should have been more specific. I am in Atlanta, GA.

This is for a project that would need more than one unit around town,
so each unit would need its own modem if thats what its called.

On another note, if cell phone technology is used, is there a way to
subscribe for data transfer only and not voice?

Thanks again,

A

 

[Leon]

I am sorry I should have been more specific. I am in Atlanta, GA.

This is for a project that would need more than one unit around town,
so each unit would need its own modem if thats what its called.

On another note, if cell phone technology is used, is there a way to
subscribe for data transfer only and not voice?

Thanks again,

A

In the UK most GSM services have both voice and data, although data
usually has to be enabled separately. There are some resellers who can
provide data only, but they can be difficult to find. You probably have
similar arrangements where you are.

I'm using Siemens M20 and TC35i GSM modem terminals for a prototype
system transmitting GPS position data to a central PC via the cellular
and PSTN networks. The GPS and GSM units are interfaced by a small MCU
board using a 16F88 PIC with two RS-232 ports.

Leon

 

[amerdsp]

Leon,
Thank you for the reply. What is the power requirement of your
current setting?
How long will it last on a single battery charge?

Best,

A

 

[Chris Hills]

I am sorry I should have been more specific. I am in Atlanta, GA.

This is for a project that would need more than one unit around town,
so each unit would need its own modem if thats what its called.

On another note, if cell phone technology is used, is there a way to
subscribe for data transfer only and not voice?

Probably.... it depends.

In the UK there are at least 4 networks that will cover any area. There
are also some specialist ones. SO I am very sure you will be able to
get a "data only" type link out of one of them. Though what it costs is
anyone's guess.

I have no idea of what it is like in Atlanta.

 

[Leon]

Leon,
Thank you for the reply. What is the power requirement of your
current setting?
How long will it last on a single battery charge?

It's just a prototype system at the moment. The final system will be
powered from vehicle battery so the consumption won't matter very much,
unless the client wants battery back-up. A similar system I designed
for use with a people counter was normally powered from a mains supply,
with a sealed lead-acid battery back-up supply. That would power it for
some days.

Leon

 

[Donald]

In the UK there are at least 4 networks that will cover any area. There
are also some specialist ones. SO I am very sure you will be able to
get a "data only" type link out of one of them. Though what it costs is
anyone's guess.

I have no idea of what it is like in Atlanta.

There are NO cell phones in the USA with data.

You have to buy a data only cell modem.

Been there, done that.

donald

 

[amerdsp]

Donald,
Can you elaborate a little about what you mean ?

Thank you,

A

 

[Geoff Field]

There are NO cell phones in the USA with data.

Cell phones often have a connector at the bottom and host software that
allows the phone be used as a "modem".

You have to buy a data only cell modem.

Can you buy a "data-only" modem? The Sony-Ericsson job we use
at work does both very nicely (and it's automotive rated). The only
problem we find is that S-E keep changing their roadmap so that,
by the time we get the project through approvals the modem is at
EOL.

Been there, done that.

So have I. Mind you, I'm doing it in Australia, where the situation
is rather more controlled. ;-)

Geoff

 

[Donald]

Cell phones often have a connector at the bottom and host software that
allows the phone be used as a "modem".




Can you buy a "data-only" modem? The Sony-Ericsson job we use
at work does both very nicely (and it's automotive rated). The only
problem we find is that S-E keep changing their roadmap so that,
by the time we get the project through approvals the modem is at
EOL.




So have I. Mind you, I'm doing it in Australia, where the situation
is rather more controlled. ;-)

Geoff

Yes, Europe and Australia ( and the middle east ) have these.

OK,

I worked for a company (6 years ago) who tried using GPS and Cell phones.

After 6 months tring to talk with the cell phone people, we found that
the cell phones sold in the USA have the modem functions disabled.
( disabled meaning that a simple serial port will not talk to it)

Some cell phones have cables so you can connect to a computer.
Well the drivers for your PC talk non-modem control codes.

ATDT1231234567 does not work.

Getting messages from a cell phone with a SMS messages does not work.

With the fear in this country about remote control bombs, etc, you can
NOT use an off the shelf cell phone and a micro serial port.

Will not work.

We ended up using a CDPD modem for that project. Now CDPD is defunct.
Company is gone too.

I doubt anyone knows of a regular cell phone that can be purchased off
the shelf anywhere in the US that has a regular serial port and AT
command set ?

If anyone does know, they will not post here. Face it, fear of the gvmt
is strong here.

http://www.sparkfun.com/commerce/categories.php?cPath=66_68

These cell phone modems do not have audio, just data.

Donald

 

[Marc Ramsey]

With the fear in this country about remote control bombs, etc, you can
NOT use an off the shelf cell phone and a micro serial port.

It has nothing to do with fear, triggering things, etc. It has to do
with *money* as does just about everything here. US cellphone companies
want to encourage you to subscribe to their expensive data services,
rather than making do with a cheap voice plan and a laptop.

If anyone does know, they will not post here. Face it, fear of the gvmt
is strong here.

Heh, I have my tinfoil hat on, I have nothing to fear 8^)

http://www.sparkfun.com/commerce/categories.php?cPath=66_68

These cell phone modems do not have audio, just data.

Read the description more carefully, these do have voice capability.
Spark Fun also offers a data-only version, but apparently these just
have defective voice circuitry...

Marc

 

[Michael A. Terrell]

Yes, Europe and Australia ( and the middle east ) have these.

OK,

I worked for a company (6 years ago) who tried using GPS and Cell phones.

After 6 months tring to talk with the cell phone people, we found that
the cell phones sold in the USA have the modem functions disabled.
( disabled meaning that a simple serial port will not talk to it)

Some cell phones have cables so you can connect to a computer.
Well the drivers for your PC talk non-modem control codes.

ATDT1231234567 does not work.

Getting messages from a cell phone with a SMS messages does not work.

With the fear in this country about remote control bombs, etc, you can
NOT use an off the shelf cell phone and a micro serial port.

Will not work.

We ended up using a CDPD modem for that project. Now CDPD is defunct.
Company is gone too.

I doubt anyone knows of a regular cell phone that can be purchased off
the shelf anywhere in the US that has a regular serial port and AT
command set ?

If anyone does know, they will not post here. Face it, fear of the gvmt
is strong here.

http://www.sparkfun.com/commerce/categories.php?cPath=66_68

These cell phone modems do not have audio, just data.

Donald

How about the combination Cell Phone and credit card terminals sold
to flea market dealers and businesses that do a lot of trade shows?


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[Leon]

It has nothing to do with fear, triggering things, etc. It has to do
with *money* as does just about everything here. US cellphone companies
want to encourage you to subscribe to their expensive data services,
rather than making do with a cheap voice plan and a laptop.


Heh, I have my tinfoil hat on, I have nothing to fear 8^)


Read the description more carefully, these do have voice capability.
Spark Fun also offers a data-only version, but apparently these just
have defective voice circuitry...

The Siemens M20 and TC35i modems have voice and data. I've got a
handset that is made for them.

GPRS is another option for telemetry that is available with the newer
modems. It has the advantage that it is always 'on', and one pays for
the amount of data transferred instead of paying for the time one is
connected. It also provides direct access to data via the Web.

Leon

 

[amerdsp]

Does anyone have any recommendation cellular CDMA/GSM modem that can be
embedded and that will work in the US? It seems finding a cellular
modem in the US is more difficult than what I thought it would be.

Maybe I am not sure what to look for. I found some modems but they are
huge and I am not sure if they work directly with a microcontroller.

Also, the remark from Donald that it will not work in the US worries me
and I am not sure I understand why. I know cars have telemetry that is
wireless, how do they do it?

Thank you all for your replies.

A

 

[Leon]

Does anyone have any recommendation cellular CDMA/GSM modem that can be
embedded and that will work in the US? It seems finding a cellular
modem in the US is more difficult than what I thought it would be.

Maybe I am not sure what to look for. I found some modems but they are
huge and I am not sure if they work directly with a microcontroller.

Also, the remark from Donald that it will not work in the US worries me
and I am not sure I understand why. I know cars have telemetry that is
wireless, how do they do it?

Thank you all for your replies.

A

Don't know about the US, but the best site for this stuff is TDC's:

http://www.tdc.co.uk/gsm/gsm_siemens.htm

Leon

 

[amerdsp]

So I have two questions:

1- GSM/GPRS modems for embedded applications available in the US I
presume. Are they not?
2 - If so, how does one go about making them work with cell phone
companies?

I know they are simple questions but I am just started learning about
all this?

 

[amerdsp]

So I have two questions:

1- GSM/GPRS modems for embedded applications available in the US I
presume. Are they not?
2 - If so, how does one go about making them work with cell phone
companies?

I know they are simple questions but I am just started learning about
all this.

Thank you,

A