GPS Receiver hardware and sketch using Tiva TM4C LaunchPad, SparkFun ZOE-M8Q GPS breakout, and CrystalFonz 8x2 LCD. The sketch is based on Example12_UseUart.ino by Nathan Seidle from the SparkFun u-blox Arduino Library.

The ZOE-M8Q I2C interface is unreliable in my setup. I am not sure if this is a problem with the hardware or the SparkFun library. This sketch uses UART to communicate between the LaunchPad and the GPS module, without issue. The Tiva TM4C LaunchPad has 8 available hardware serial ports. This sketch uses UART module 1 (accessed using the "Serial1" object). Debug information is sent through the usual "Serial" USB backchannel.

The LCD display cycles between several GPS data values (lat/long, altitude, # satellites, ground speed, date/time). Hold down "SW1" on the LaunchPad to freeze the display at the current reading.

The GPS can LCD are connected to the LaunchPad as follows:

LaunchPad   GPS  LCD    Signal Name
---------   ---  ---  ----------------
     1       4          3V3
     2       
     3       2          LP RX1 <- GPS TXO
     4       3          LP TX1 -> GPS RXI
     5
     6
     7
     8
     9       7          SCL (This sketch does not use I2C)
    10       8          SDA (This sketch does not use I2C)
    11           4      RS
    12           6      E
    13          11      DB4
    14          12      DB5
    15          13      DB6
    16
    17
    18          14      DB7
    19
    20      6    1,5    GND (LCD pin 5 is R/W*)
    21           2      +5V (VDD)
                 3      Vo (wiper pin on 10K pot tied between +5V and GND)

• SparkFun u-blox Arduino Library

  This sketch uses SparkFun's u-blox Arduino library. That library has since been deprecated and replaced with SparkFun's u-blox GNSS library. Migrating to the new library requires some minor sketch updates as outlined here.

• SparkFun ZOE-M8Q GPS Breakout
• Texas Instruments TM4C LaunchPad
  • Embedded Computing pinout diagram
  • Note that RX1/TX1 on pins 37/36 should be labeled as RX4/TX4
• CrystalFonz LCD
  • datasheet

The software and other files in this repository are released under what is commonly called the MIT License. See the file LICENSE in this repository.