8545-0198-01 Revision 1.9 STX3 Users Manual
9/24/2020 Globalstar, Inc. Confidential and Proprietary Page | 15
5 Application Programming Interface
5.1 Serial Port
A half-duplex (0-3.0V) TTL asynchronous serial port (UART) is the primary interface to the user equipment. The serial port operates
with the serial parameters of 9600bps, 8 data bits, no parity, 1 stop bit.
The RX data input and the RTS inputs are 5V tolerant. The TX data and CTS outputs are 0-3.0V TTL.
RS232 input levels are not supported. RS232 data must be converted to TTL before being sent to the unit.
Each command from the DTE to the modem (STX) is sent in a serial packet. Upon receiving the command, the modem answers to the
DTE and, if applicable, executes the command.
In order to wake up the modem (STX) from sleep mode and to indicate the end of the serial packet, each serial packet must be
framed by activating RTS before the first byte of the command and deactivating RTS after the last byte of the command.
5.2 Serial Packet Mode
This mode is the legacy mode of operation as implemented in the STX2 which consists of binary data packets.
To Next Page
Loading...
