I am trying to test a sim900 in NYC for use in another country. It has been tested there, where 4G IOT is not yet available and functions properly.
Reading this article I am unclear if new sims can be activated on a 2G network in New York.
Fona 808 another GPRS module is first on the list of compatiability here, but not specific to region.
Trying with two different sim900 boards, using FTDI cable for serial and 5V 3A power supply to power the boards.
AT OK AT+CPIN? +CPIN: READY OK AT+CSQ +CSQ: 0,0 OK AT+CBAND? +CBAND: INVALID_BAND_MODE,ALL_BAND OK AT+CMGF=1 OK AT+CIPSHUT SHUT OK AT+CSQ +CSQ: 0,0 OK AT+CGATT? +CGATT: 0 OK AT+CGATT=1 ERROR AT+CIPMUX=1 OK AT+CSTT="hologram" ERROR AT+CIICR ERROR AT+CIFSR ERROR
+CSQ: 0,0 is particularly concerning. Getting this with two different modules.
Firmware version was updated recently,
AT+GSV SIMCOM_Ltd SIMCOM_SIM900 Revision:1137B06SIM900M64_ST_ENHANCE OK
AT+COPS=? +COPS: ,,(0,1,4),(0,2) OK
Using sim7000 or a 4G cell phone the sim cards connect so they are activated properly.