First off, I am a complete newbie with everything related to sim cards and mobile carriers. Please forgive any stupid questions
I am designing a product with a very simple micro controller communicating to a NimbeLink cell modem with a Hologram sim card. The goal is to use this system anywhere in the U.S. to send occasional SMS messages. Communication to the cell modem is working well and sometimes I can send the SMS through the system (using “AT+CMGS=” command) but sometimes the cell modem simply can’t send the SMS. I suspect some cell carriers allow SMS messages but some don’t. Are there only certain carriers which are able to do this? If only carriers allow SMS messages, is it possible to configure the modem to only use those carriers?
Thanks in advance!