Sending UDM message from Raspberry via SIM900a GPRS module in python. 1nce provider

Question

I'm trying to send a UDP message via GPRS service from Raspberry but nothing happens. Here is my code. Any advice? Sorry, but this is my first question on StackOverflow. Thanks

import time
import serial
def receive(ser):
 print("READ:")
 time.sleep(1)
 data_left = ser.inWaiting()
 while data_left > 0:
 received_data = ser.read() #read serial port
 time.sleep(0.3)
 data_left = ser.inWaiting() #check for remaining byte
 received_data += ser.read(data_left)
 print(received_data)
ser = serial.Serial("/dev/ttyS0", 9600)
time.sleep(1)
ser.write("AT+CGATT = 1".encode())
receive(ser)
ser.write("AT+CSTT=\"iot.1nce.net\"".encode())
receive(ser)
ser.write("AT+CIICR".encode())
receive(ser)
ser.write("AT+CIFSR".encode())
receive(ser)
ser.write("AT+CIPSTART=\"UDP\",\"100.22.34.22\",8000".encode())
receive(ser)
ser.write("AT+CIPSEND".encode())
receive(ser)
ser.write(("{\"testo\":\"12345\"}" + chr(26)).encode())
receive(ser)

• goldilocks: You might want to clarify what you mean by "UDM" and "UDP" message -- I suspect one or both of these is a typo and may confuse the issue a bit.
• diego n: yes is a typo. I meant UDP
• goldilocks: Ah, okay. I missed the CIPSTART line, did not realize you could send UDP packets that way.

Answer 1

Please check out your power supply. SIM900A needs 5V,2A. If the voltage or current is not sufficient, it will not function.

• diego n: The sim900a is powered by a separate PSU at 4V and can provide 60 watt. The sim900a device should work from 3.6 to 4.5V