You can use the standard, HW UART on the Raspberry Pi to capture UART data.
In addition to this standard UART, as demonstrated below, you can use two GPIO pins on the Raspberry Pi to “Bit Bang” data in or as a “Software Serial” port rather than needing a 2nd Hardware one (that isn’t broken out).
The below software Serial port utilizes the great PIGPIO Library which you can download and install for free at the following URL: PIGPIO Library
Here’s the code I got working with the SparqEE GPS module running at 9600baud and the installation on the Raspberry Pi:
Execute this code on the Raspberry Pi to install:
wget abyz.co.uk/rpi/pigpio/pigpio.zip
unzip pigpio.zip
cd PIGPIO
make
sudo make install
Here’s the python code. Put it into a file such as “test.py,” change the permissions of the file “chmod 755 test.py,” then execute the script “./test.py”
With this code I simply wanted to input some GPS NMEA strings into the RasPi and print them out. I used GPIO pin 18 for the Receive (RX) side of the GPS device.
#!/usr/bin/python
import sys
import time
import difflib
import pigpio
RX=18
try:
pi = pigpio.pi()
pi.set_mode(RX, pigpio.INPUT)
pi.bb_serial_read_open(RX, 9600, 8)
print "DATA - SOFTWARE SERIAL:"
while 1:
(count, data) = pi.bb_serial_read(RX)
if count:
print data
time.sleep(1)
except:
pi.bb_serial_read_close(RX)
pi.stop()
