Gsmneo

Always test your GSMNeo with a simple loopback first: connect TX to RX via a resistor divider and send AT . If you get AT back, your serial communication works. Then add the SIM and antenna.

AT+CMGS="+1234567890" > ALERT: Water leak detected in basement.␛ gsmneo

If GSMNeo refers to a specific device or software tool you had in mind, please reply with more details so I can tailor the article precisely. Always test your GSMNeo with a simple loopback

Given the ambiguity around "GSM-NEO," I'll provide an overview of GSM, which is a well-defined and widely used technology: gsmneo