FAQ forum/wiki?

[davidc]

Another one: Connecting to I/O pins on Q2686 etc

viewtopic.php?f=29&t=3942&start=0
viewtopic.php?f=78&t=3946&start=0

ciao, Dave

[awneil]

viewtopic.php?f=5&t=3941&p=15544#p15544
viewtopic.php?f=21&t=3950&p=15542#p15542

[awneil]

atd99**1#
CONNECT 115200
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NO CARRIER

1. Why this NO CARRIER is comming?

eg, viewtopic.php?f=37&t=3986&p=15720#p15717
viewtopic.php?f=30&t=2275&p=9244#p8408

It’s not “garbage” - it is PPP data.
The module has been asked to create an IP connection, so it expects the external device to respond with IP packets in PPP format.
Because it doesn’t get any PPP/IP packets, it drops the call - hence giving NO CARRIER.

The modem is working correctly!

[davidc]

Hiya,

Don’t use the following code construct:

while(1)
{
    // do something
}

See viewtopic.php?f=36&t=3908&start=15#p16093 amongst others.

ciao, Dave

[awneil]

• The dependence of certain facilities on having specifc “Commercial Features” enabled;

See also: viewtopic.php?f=23&t=3922&p=16688#p15350

Example: viewtopic.php?f=16&t=4204&p=16686#p16686

[davidc]

Hiya,

Looks like a number of users are having strange or intermittent issues with their modules that end up being resolved by fixing the module PSU.

See here and here for a couple of examples.

Of course, there’s also the Power Supply forum to peruse as well.

ciao, Dave

[awneil]

Looks like a number of users are having strange or intermittent issues with their modules that end up being resolved by fixing the module PSU.

Yes, I’ve had such issues myself!

It’s not just the PSU itself - the connections to the module (especially ground) need to be absolutely “solid”

Example: viewtopic.php?f=123&t=5693&p=23827&hilit=vbatt+line+too+narrow#p23826

This is because all GSM devices have a very high supply current peaks - Wavecom quote over 2A!

Edit:
Just noted that I have already mentioned “Module Grounding” in an earlier suggestion in this thread!

[awneil]

An increasing number of people are now asking about C++

eg,

viewtopic.php?f=19&t=4146&p=16728#p16728

viewtopic.php?f=78&t=4201&p=16652#p16626

viewtopic.php?f=78&t=3082&p=12149&hilit=extern#p12149

[awneil]

• The dependence of certain facilities on having specifc “Commercial Features” enabled;

See also: viewtopic.php?f=23&t=3922&p=16688#p15350

Example: viewtopic.php?f=16&t=4204&p=16686#p16686

Another example: viewtopic.php?f=74&t=4252&p=17077#p17075

[awneil]

An increasing number of people are now asking about C++

eg,

viewtopic.php?f=19&t=4146&p=16728#p16728

viewtopic.php?f=78&t=4201&p=16652#p16626

viewtopic.php?f=78&t=3082&p=12149&hilit=extern#p12149

And another: viewtopic.php?f=78&t=4285&p=17090#p17088

[awneil]

If the unit fails to register, check the Frequency Band setting - especially after a firmware update

see: viewtopic.php?f=53&t=4332#p17345

[awneil]

The need to enable USB (and UART2) before it can be used:

viewtopic.php?f=29&t=3948&p=15518#p15518

But note that R7.4 opens the USB port automatically - this is a change from earlier firmware.

[davidc]

Hiya,

Yet another common problem: Trying to make calls/connect to GPRS before SIM is initalised and network registered.

Always check SIM state and Network Registration before attempting network operations.

Check for SIM_FULL_INIT and +CREG: 1 responses…

See:
viewtopic.php?f=3&t=3422
viewtopic.php?f=29&t=3975
for a couple of examples

ciao, Dave

[awneil]

Trying to make calls/connect to GPRS before SIM is initalised and network registered.

In fact, trying to do anything network-related before the network is ready!

SMS is another key one…

This one, of course, is not Wavecom-specific.

[awneil]

The need to enable USB (and UART2) before it can be used:

viewtopic.php?f=78&t=4477&p=18038#p18038

[awneil]

• The trick of having a startup delay in your application - and all samples should do this

For example, see:
viewtopic.php?f=29&t=3621&p=14446&hilit=startup+delay#p14446

viewtopic.php?f=30&t=3227&p=12032&hilit=delay+startup#p12032

viewtopic.php?f=30&t=3227&p=12032&hilit=delay+startup#p12032

[Madouc]

• The trick of having a startup delay in your application - and all samples should do this

For example, see:
viewtopic.php?f=29&t=3621&p=14446&hilit=startup+delay#p14446

viewtopic.php?f=30&t=3227&p=12032&hilit=delay+startup#p12032

viewtopic.php?f=30&t=3227&p=12032&hilit=delay+startup#p12032

i don’t know if i agree entirely,
the latest firmware editions try to start you application 8 times and if it still crashes the 8th time, they give up on it.

[awneil]

the latest firmware editions

What editions, specifically?

try to start you application 8 times and if it still crashes the 8th time, they give up on it.

Is that actually documented?

But there are still people using firmware versions without this feature: viewtopic.php?f=19&t=4486

[Madouc]

the latest firmware editions

What editions, specifically?

i’m fairly certain that this mechanism is functional since 7.x

try to start you application 8 times and if it still crashes the 8th time, they give up on it.

Is that actually documented?

yes, see ‘Description / Recovery Mechanism’ in the ADL user guide

But there are still people using firmware versions without this feature: viewtopic.php?f=19&t=4486

i know, and for these people it’s still helpful.

[awneil]

The requirement that an application has to be built for a firmware version that matches the firmware physically installed on the device.
(in general, “matches” means “the same as”).

It’s a bit like making an application for a PC: if you build the application to run on Vista, it won’t work on Win-95

The response to AT+WOPEN=2 shows both the firmware version physically installed on the device, and the version for which the currently-loaded application was built:

+WOPEN: 2,“AT v06.00”,“AT v06.31”

In general, the two numbers need to be the same.

Examples:
viewtopic.php?f=78&t=4501&p=18139#p18139
viewtopic.php?f=78&t=4390&p=17817#p17817