HD53GSM is a wireless quad-band GSM/GPRS modem. The module is controlled via standard RS232 serial interface and AT commands.
- SIM card slot,
- SMA antenna connector,
- power line connector with remote on/off line,
- two status LED: the POWER LED is switched on when the GSM is powered, the NET LED indicates the connection status to the GSM net,
- RS232 Sub-D 9-pin connector.