Parallax GPS Smart Mode

Forum 2005-2010 (read only) Software Interfacing
10

For anyone else that needs the information.

When the TX pin on the Arduino goes into its idle state, it will assert itself HIGH. By doing this, it will inhibit the GPS from ever responding.

To solve this issue, you need to connect a diode as follows:

  1. Connect the TX Pin of the Arduino the anode side of a standard 1N914 diode

  2. Connect the RX Pin of the Arduino the cathode side of the diode

  3. Connect the SIO Pin of the GPS to the cathode side of the diode

TX Pin -->|-- RX Pin ---- SIO on GPS

anode -->|-- cathode (diode)

---- (wire)

All credit for this goes to Mike Green of the parallax forums who can be found here:
http://forums.parallax.com/forums/profile.aspx?f=15&m=436519&p=1453