Testing a GSM module via Mecanique's Serial Communicator - "terminator" issue?

Hi All,

I'm currently testing a SIM800L GSM module and have no probelm at all to make it work via my 18f2431 PIC.

So, what's the problem?

In fact, I want to make this module work also via the Serial Comunicator from Mecanique but this seems just not possible.

Here is an example of a SMS message I want to send:

working with PIC: SEROUT PORTB.4,2,["AT+CMGS=",34,"+4179xxxxxx",34,10,"Hello Roger",26,10,13]

not working with serial com: "AT+CMGS="+4179xxxxxxx",10,"Hello Roger",26

Going back to basics, when I send a simple AT command and set the Serial Communicator to add a CR terminator, it will work.

If I select "no terminator" and try it like this AT,13 , nothing will happen.

How is the CR generated in the Serial Communicator? Does anyone know?

When you type AT 13 (without the comma), the terminal will send 4 sequence of the ASCII equivalent (in decimal): 65 84 49 51. This is not what you want, right?

You want the number 13 be sent, not the 49 ('1') and 51 ('3').

Hope this helps,
Ioannis

"AT+CMGS="+4179xxxxxxx",#10,"Hello Roger",#26


or

"AT+CMGS="+4179xxxxxxx",$A,"Hello Roger",$1A

Attachment 8888

To add on Richard's post, if you insist on using the Serial Communicator, Help says this:

Parse Control Characters

When enabled, the parse control characters option enables you to send control characters in your message, using either a decimal or hexadecimal notation. For example, if you want to send hello world followed by a carriage return and line feed character, you would use hello world#13#10 for decimal, or hello world$D$A for hex. Only numbers in the range 0 to 255 will be converted. For example, sending the message letter #9712345 will be interpreted as letter a12345.

If the sequence of characters does not form a legal number, the sequence is interpreted as normal characters. For example, hello world#here I am. If you don't want characters to be interpreted as a control sequence, but rather send it as normal characters, then all you need to do is use the tilda symbol (~). For example, letter ~#9712345 would be sent as letter #9712345.


Ioannis

Thanks guys,

I knew it, I knew it!!! :D

I should have read the communicator's help again - did it a few years ago but forgot the "hash" story... my bad :-\

Thanks again...

Quote:

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Originally Posted by Ioannis

When you type AT 13 (without the comma), the terminal will send 4 sequence of the ASCII equivalent (in decimal): 65 84 49 51. This is not what you want, right?

You want the number 13 be sent, not the 49 ('1') and 51 ('3')....

---

Thanks Ioannis for this good lesson. I effectively didn't realize that I was sending those "four individual" characters one-by-one.

Have a nice day :)

You are welcome!

Ioannis

Quote:

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Originally Posted by richard

"AT+CMGS="+4179xxxxxxx",#10,"Hello Roger",#26

---

Actually, the working syntax in the Serial Communicator is: AT+CMGS="+4179xxxxxxx"#10"Hello Roger"#26

Thanks Richard for your help :wink:

BTW, one of the AT commands manual I could find in the WEB says:

Attachment 8891

Using the SIM800L GSM module, according to the "AT data sheet" (:D) I should have used a CR after the phone number. But by chance, I discovered that only a LF would work. Is it a typo or something wrong with my module, I don't know; fact is CR = NO, LF = YES!!!!

I never faced such a problem with SIMcom modules.

CR is the necessary for line or command termination. LF does not that...

Are absolutely sure you send out LF instead of CR?

Ioannis

Ioannis,

This is really strange, yes. It took me hours to find out that there was something strange.

But actually, to make it work, I use:

working with PIC: SEROUT PORTB.4,2,["AT+CMGS=",34,"+4179xxxxxx",34,10,"Hello Roger",26,10,13]

working with serial com: AT+CMGS="+4179xxxxxxx"#10"Hello Roger"#26

If I replace the 10 or #10 by a 13 or #13, it will not work anymore.

Nope, no idea what's wrong but "yes", I'm sure I use LF instead of CR.

Sure is sure so I just checked again.

See whats happens with CR instead of LF:

Attachment 8892

Do you have other terminal program to test? My suspicions fall on MCSP serial communicator.

Ioannis

I'll give it a try with PUTTY and HYPERTERMINAL although I don't know how to send control characters with those programs too :(

But why would it be the problem of my serial program since I need to do the same when I use the PIC?

working with PIC: SEROUT PORTB.4,2,["AT+CMGS=",34,"+4179xxxxxx",34,10,"Hello Roger",26,10,13]

As you can see, here too I need to use a Line Feed instead of a Carriage Return !?

You are right.I missed that.

Well, I don't know what is wrong. I remember once, was testing on a SIM900 module with no problems on this. Sure a CR was needed to terminate the command.

For a couple of days I'll be out of town. On my return I will find it and give it a test again.

Ioannis

My module's firmware is Revision:1418B02SIM800L24

...and this the exact module I'm using.

Attachment 8893

Finally I found the module and time to test the SIM900 board.

Unfortunatelly, while on Power up the module sends what is expected to send, it does not respond to the commands I send.

Tried any combination but failed to reply back...

Sorry but could not help.

Ioannis

Thank you Ioannis.

I'm awaiting a SIM5360EVB and I will try again if the LF or CR makes the difference.