How I managed to use the L80 Microstack GPS and avoides to buy the unnecessary base shield.
Despite the manufacturer recomendation, we don’t need to buy the additional shield to make the microstack GPS work on the raspberry pi. The L80 GPS datasheet  shows that the module has an UART port, and the only function provided by the microstack base shield is purely interconections between the module and the raspberry pi UART.
Rasberry Pi Configuration
The first step is to reconfigure the serial port, closing the default terminal output:
select Advanced Options -> Serial
and it’s done! Now we have a Serial port inteface for peripherals.
As the datasheet says, there’s only 4 pins that you gonna need for a basic interface:
- Serial_MTXSRX (master transmitter slave receiver)
- Serial_MRXSTX (master receiver slave transmitter)
From the “datasheet” :
The 3V3 and GND pins can be connected to pin 1 and pin 6, respectively. MTXSRX must be connected to pin 8 and MRXSTX to pin 10, as indicated in yellow in the following image:
Now that we got everything interconnected and ready to talk, let’s use the strengths of linux: ready-to-go drivers and aplications programs. In our case, the best program to use is gpsd .
…to be continued.