How to send SMS with SIM800?

[Sergejs]

I can not send sms. I open text mode with AT+CMGF=1 and than I can not send sms or escape from this mode. I must put out battery for reseting module. Can I get example how to send SMS in V9 please?

[chipfryer27]

Hi

If you do a search in the forums (check "old" forums too) there are plenty of examples. Also, post your current chart so we can see what is going wrong to help.

Regards

[Sergejs]

Hi

If you do a search in the forums (check "old" forums too) there are plenty of examples. Also, post your current chart so we can see what is going wrong to help.

Regards

Here it is my project:

SIM800C_883.fcfx

(15.19 KiB) Downloaded 348 times

[chipfryer27]

Hi

I've had a quick look at your chart. Is there any reason you are trying to communicate with the SIM800 at 19200 baud? Is your module preset to use that speed? I ask as I think it's default is 9600 (or possibly 115200).

I see you are using the UART to send commands but you need to allow time for the module to process the command before you issue any further. This can be achieved by waiting until the module sends you the correct reply.

If using the UART, to establish what commands you need to send, it is a good idea to simply connect your PC running a Terminal program to the module using a USB-TTL Serial converter. When you send "AT" you should get a reply of "OK". You can then send commands to configure / control, noting the order as you progress. This would then form the basis of your chart.

About a year ago I tested one to update ThingSpeak and used the UART and Circular Buffer. This topic may help.

https://www.matrixtsl.com/mmforums/view ... 71#p106871

Regards

[Sergejs]

Thanks for look at my project, in terminal it works only at 19200 bod. But there is command to finish and in terminal it works but not in Flowcode. Here it is:

I found it in Google and I do not know how it convert to use in Flowcode. It just not understand this command to finish SMS MODE. This is the problem. But not in terminal USB-TTL. This stops me to continue. May do you know any other command how to escape from text mode to usual modem mode?

With regards.

[chipfryer27]

Hi

If you read through the link above you will see I document the AT commands and expected replies to connect and control. I also provide an example chart showing each step in the process that can be modified. Whilst the chart works, it's main purpose was to "prove" each step before moving on. Once happy with the result I could then tidy it up.

I may have an example of sending SMS but not to hand.

Regards

PS
I'd recommend you do a search for SIM800 AT Commands and download a copy as that documents how to use each command and expected reply (if any)