Globalstar STX3, Руководство пользователя

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USB INTERFACE
For the Dev Kit, the micro-USB connector provides power and serial communications for the command terminal.
The USB data signals are converted to UART signals (TX, RX, RTS, and CTS) with an FTDI device (manufacturer
part number FT234XD). The UART signals from the FTDI device are connected to the processor.
The Dev Kit does not require the USB data signals for functionality, it is only required when communicating with the
host computer using serial commands. The proper power must be connected to the USB connector for the Dev Kit
to function properly.
CONNECTOR INTERFACES
The Dev Kit includes multiple connectors that interface the Main board with the Transmitter board and other
connector interfaces.
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Transmitter board interfaces - There are two 1x7 headers (J3, J4) that provide the interface signals between
the Main and Transmitter boards. These signals include power, UART signals, STX3 configuration, and STX3
reset. The Transmitter board also has an unpopulated 1x6 header (J1) that allows for connecting the Transmitter
board to an off-board processor. A separate unpopulated 2x3 header (J2) allows for the Transmitter board to be
connected to an off-board power source.
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Main board interfaces - Aside from the micro-USB, there is the 2x10 JTAG header (J10), 2x6 header (J8) for
expansion and the two 1x7 socket (J7, J9) for interfacing to the Transmitter board.
TEST POINTS
The Dev Kit includes a total of 39 test points spread across the Transmitter and Main boards. Many of the test points
are connected to digital signals on the processor and STX3 module. There is also an array of test points that support
monitoring of voltages and options for monitoring current. In the schematic, the test points will have reference
designators with TPxx or TPSxx. The TPxx test points are labeled and are through holes on the PCB. The TPSxx test
point is a surface mount pad on the PCB. Please refer to the full schematic for connections of each test point and
PCB layout for the location of the test points.