I want to send an information to web server with arduino via sim800l.
AT+HTTPPARA=\"URL\",\"http://api.trackers.live/v3.0.0/TRCKR02B2AF359D19/40.35715122342342322432-36.077406243242342-1469134234/1212/021/16553"
When I want to send long url to web server,the program crashes.
Does sim800l has an url limit? or is there any possible way to send an url like this?
Yes, all modems have a limit in how many characters they accept on a command line. The V.250 specification says in chapter "5.2.1 Command line general format":
A command line is made up of three elements: the prefix, the body, and the termination character. ... The DCE shall be capable of accepting at least 40 characters in the body.
The prefix is the two characters "AT" or "at" and the termination character should be '\r', thus a modem (aka DCE, Data Circuit-terminating Equipment) is allowed to only accept as low as 43 characters on a command line.
Now the was majority of modem supports more, probably that 40 character limit was due to some old Hayes modem made in the 1970s. If sim800l has decent documentation it should say how many characters it support on a command line. If it has crappy documentation it will not say.
As always with AT command syntax question, the very first source to query should always be the manufacturer specific documentation for that particular modem. Failing that you can fall back to V.250 or 27.007 or 27.005.
I dont know about the limit but you can use a link shortener to shorten the link...
Related
I am sending commands over a serial port from a Linux embedded device to some serial enabled firmware. For easy debugging and simplicity we are using ascii human-readable commands terminated by newlines. Is it appropriate to use canonical mode here, or is canonical mode usually reserved for interactive terminals? The examples I find online all use raw mode.
In particular, in canonical mode, how do I check without blocking if an entire line is available for reading.
according to Linux Serial Programming documentation :
This is the normal processing mode for terminals, but can also be useful for
communicating with other dl input is processed in units of lines, which means
that a read will only return a full line of input. A line is by default
terminated by a NL (ASCII LF), an end of file, or an end of line character. A
CR (the DOS/Windows default end-of-line) will not terminate a line with the
default settings.
Canonical input processing can also handle the erase, delete word, and
reprint characters, translate CR to NL, etc..
First
using canonical mode for serial communications is the best option, because we have Linux kernel support on data transmission and system handlers that will help to better reading serial text
Second
if you want to use canonical mode , make sure that you are using the right character for end of line in your device that sending data , other way you cannot use canonical feature
Is it appropriate to use canonical mode here, or is canonical mode usually reserved for interactive terminals?
Yes, you can use canonical mode, but you will need to configure the termios interface for your situation.
The default termios configuration is for an interactive terminal, so features such as echoing the input should be disabled.
Since your device is unlikely to send the backspace and delete characters, such features can be ignored.
The examples I find online all use raw mode.
Seems like there are some "experts" that are not aware that canonical mode for terminals exists.
See the comments to reading from serial port in c breaks up lines .
For an example of (blocking) canonical mode, see this answer (note that there's another "expert comment" telling the OP that he cannot read lines).
In particular, in canonical mode, how do I check without blocking if an entire line is available for reading.
You could use select().
The man page implies that a canonical read of a terminal device is supported:
The file descriptors listed in readfds will be watched to see if characters become available for reading (more precisely, to see if a read will not block ...)
When both fields of the timeval structure are zero, then select() will not block and returns immediately.
I am broadcasting Hello using one Xbee (say A).....Xbee (say B) and Xbee (say C) are receiving a lot of garbage values before and after Hello.
All the baudrates are 9600...where am I going wrong?
It would help if you posted an example of the data you see, perhaps the hex values of each byte.
My guess is that you've configured the modules for "API mode" which wraps payloads with a header (starting with 0x7E, the character ~) and footer. It's useful for "smart" devices because it supports multiple packet types.
Check your settings, and make sure you're using ATAP=0. You can use XCTU to change the settings, or from a terminal use the escape sequence (1 second pause, +++, 1 second pause then module should respond with OK) to enter command mode. In command mode, first set ATAP0 and then ATWR to save the changes.
I would like to receive and send bytes that have special meaning in ASCII code like End of Text, End of Transmission etc. but I am not sure if it is allowed. Can it break my communication? Sending and receiving looks like reading from file that is why I doubt I can directly use this specific values. I use Windows OS.
EDIT: I have tested it and there is no problem with any sign. All of control ASCII characters can be sent via RS 232. Both reading and writing cause no unexpected behaviour.
RS232 is a very binary protocol. It does not even assume 8-bit bytes, let alone ASCII. The fact that on Windows, you use file functions does not matter either. Those too do not assume text data, although those do assume 8-bit byets.
RS-232 nodes do not interpret the data except in software flow control mode (XOn/XOff). You use this mode only if both parties agree and agree on the values of XOn and XOff.
The values are historically based on the ASCII DC1 and DC3 characters but the only thing that matters is their values, 0x11, and 0x13.
If you haven't set up software flow control, all values are passed through as-is.
I am currently implementing an EDI solution in BizTalk Server 2010.
This is the scenario:
BizTalk is responsible for the correct message routing between a X.400 mailbox and the customer's ERP software. It is also used to put information about the exchanged message into a SharePoint site using the SharePoint webservices.
I am using Role Links and the BizTalk party management to apply the correct settings (send ports, password in UNB6 segment, etc.).
Now I have the following question:
When I try to fetch an outgoing INVOIC message from the customer's ERP system, extract the relevant information in an orchestration and write it into the SharePoint site, the receive port using the EDI receive pipeline gets suspended with the following error message:
An output message of the component "EDI disassembler" in receive pipeline
"**********.Pipelines.FileNamePromotionEDIReceivePipeline, **********.Pipelines,
Version=1.0.0.0, Culture=neutral, PublicKeyToken=****************" is suspended
due to the following error:
Error: 1 (Miscellaneous error)
33: Invalid occurence outside message, package or group.
The sequence number of the suspended message is 1.
This happens because the message uses a CR and LF as suffix after each segment delimiter. Now I could add the ASCII-hex-codes for CR and LF to the "EfactDelimiters" setting of the pipeline, but the problem is that there are other messages without the CR and LF, which then could not be received using the same pipeline. By the way, when I fetch one of those messages without CR and LF using the pipeline also without CR and LF set as delimiters, the receive port also gets suspended, this time with an error message resulting from the usage of dots instead of commas as decimal separator (although I have enabled the option "UseDotAsDecimalSeparator" in the pipeline). Again, only changing the EfactDelimiters helps.
I thought that the "Character set and separators" page in the party agreement was supposed to make exactly that possible: To set the delimiters individually for each business party. But the changes I make in these settings seem to have no effect whatsoever. I set the "UNA6 Suffix" to "CR LF" and the "Decimal Notation (UNA3)" to ".(Decimal)", restart the host instance... same problem.
Can anyone help?
I never used biztalk, but I know my EDIFACT, and as far as I know, those messages containing CR/LF are syntactically wrong. The UNA6 Suffix seems to be an addition by Microsoft, as I can find no trace of it in the official documents on EDIFACT at UNECE.
Normally, the chars you want to use as special chars in an EDIFACT message are set by the special (optinal) UNA segment, which always comes first. When you write, you set the separators / delimiters, I don't really know, what you mean by that, as it could refer either to setting the options for the created message (what delimiters are used in the message), setting the delimiters used for parsing by the receiving program, or it could refer to the chars that are printed in the UNA segment.
Know, in the UNA segment, there is no way that I know of, to indicate the use of any UNA6 suffix (as stated quite explicitly in the documents, the UNA segment has to be exactly 9 characters of length, see 8.3 Interchange formatting rules). That leads me to the conclusion, that you set the options for the created messages. I would not advise to use a UNA6 suffix, if you can avoid it. It might be nice for humans to read the message, but it does not belong there and is not useful for the machine to read.
If the receiving program has no option to allow optional occurrence of CR/LF, and you can not avoid a mix of those to kind of messages, I see no other way for you other than somehow insert a small program that gets rid of the CR/LF.
The most important principle is of course, to make the sending and the receiving program talk in the same syntax, otherwise it can't work. The same thing goes for the problem with the decimal separator. As of Syntax rules, 10.1, either the comma or the dot is allowed, which is a quite loose definition. If you want to be on the save side, send an UNA segment, specifying which one you use, and then only use that one.
I'm not really sure, how much this helps you with the specific problem, as it might be a thing that's only a question on how to configure biztalk, but I thing some background information should be useful.
Im working on a program to send and recieve SMS using a GSM modem and my computer.
I have gotten sending and receiving to work - well sort of.
Once in a while my program is sent into a total chrash due to modem is mixing up information about Radio Signal Strength Indication and alike, while also serving my program with the hex code for the message.
My code can handle the hex code just fine. but I have seen the following line popup while im decoding a byte stream:
^RSSI: 2
So far I've seen it send out values between 1 and 10.
Is there an AT Command that can disable them? I have no need for them.
Or alternative: Is there a general syntax for them, so I can filter them out before decoding?
Im leaning towards a filter solution. But that would be more easy to implement if I knew whenever modem is sending out on the form: "^SOMETHING: xxx", then It would be nice to know if it is always followed up be a delimiter say for instance "\r".
You should try turning off periodic messages as using AT^CURC=0.
Information regarding the AT^CURC command:
AT^CURC? Current setting of periodic status messages
AT^CURC=? See what you possible values are
AT^CURC=0 turn off periodic status messages
The best way to tackle this scenario would be to replace that part of the response with an empty string because otherwise, it will be difficult to check even if the command sent to disable it is working or not.
This regex will match all those. You can replace them ideally by an empty string.
(\\n|\\r|\\r\\n)\\^.*(\\n|\\r|\\r\\n)