Sooner or later, someone is going to ask about a longer cable to connect their GPS to the UAV DevBoard.I am hoping that, sooner or later, someone will offer a longer cable with the correct connectors, maybe they do already, and I just don't about it. If anyone knows of one, please let me know. I have asked SparkFun to offer one, but right not they don't have one.In the meantime, there is another GPS connection option with the DevBoard. There is a spare USART connected to the spare pins. You could connect your GPS to 5V, ground, TX and RX on the "debug" port and revise the firwmare to use the spare USART. However, please be aware that the dsPIC30F4011 pins are 5 volt Schmidt triggers. This means that you cannot connect most GPS receivers directly to the spare TX and RX pins and expect them to work, particularly if they are 3.3 volt receivers. You may have to provide signal level shifting in both directions. Even the EM406 requires a "boost" to 5 volts on the signal going from the GPS to the dsPIC. This is because although the EM406 uses a 5 volt power supply, its TX pin only goes up to 3.8 volts, which is not high enough for a 5 volt Schmidt trigger. So, if you decide to connect an EM406 GPS to the spare port, you will need provide a signal level shifter similar to the one shown on the DevBoard schematic.
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