hi how can i send and receive on module GSM sim 800l.
i put TX/RX pins from module to TX/RX raspberry pi.
but i receive nothing from module.
actually i don't know how its works.
can someone help me to figure it out ?
i searching for it: How to send temperature data using GSM SIM900 Module to Node-RED
call pin in my gsm module work fine but my serial connection did not work.
when i call or send sms to my sim show 0 or 1 in debug.
no one can help me in here ?
Can you talk to the module without using node-red ? Eg using picocom terminal ? Have you got to and Rex crossed correctly ?
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as i have rapberry pi 3 i must enbale: aurt and ttys0 serial port
in picocom it say:
pi@raspberrypi:~ $ sudo picocom --baud 1200 /dev/ttyS0
picocom v3.1
port is : /dev/ttyS0
flowcontrol : none
baudrate is : 1200
parity is : none
databits are : 8
stopbits are : 1
escape is : C-a
local echo is : no
noinit is : no
noreset is : no
hangup is : no
nolock is : no
send_cmd is : sz -vv
receive_cmd is : rz -vv -E
imap is :
omap is :
emap is : crcrlf,delbs,
logfile is : none
initstring : none
exit_after is : not set
exit is : no
Type [C-a] [C-h] to see available commands
Terminal ready
but i cant type command AT in terminal. why ?
the terminal will show what comes back from the modem - if echo isn't turned on you may not see what you send. If you type ATZ then you should get something back. If not then either the baud rate is wrong or you have the wrong port, or you have wired it up incorrectly. I'm afraid you will have to debug it - it's not really a Node-RED issue.
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ok its work right now with USB serial Module. and its responding.
now, how can i send command to it, like picocom in node-red?
Yes - probably easiest to start with the serial-request node - that will send a command and wait for an answer. Make sure picocom isn't running at the same time.
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TY. one more question.
how to perform ctrl+z in node-red ?
is that have a command or any method for ESC from typing MSG ?
as you know after type msg, you must perform CTRL + Z to send that msg.
If you really need to add ctrl-z to everything then set the output to add character 0x1a - which is ctrl-z (char 26)
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this character will drop all commands in module.
can i send it as msg.payload to serial in function node ?
did you read my question ? its not my answer.
Yes of course you can.
msg.payload = msg.payload + "\u001a";
return msg;
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thank you @dceejay. its worked.
Hi, sir can you share the flow???? its look something very useful for my project, or its the same...Thanks in advance.
