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Gallop43 Expansion Board

LCD Side of Board

The Gallop43 expansion board offers numerous features to help you make the most of your Overo COM. This discussion will begin with closeup photos of various parts of the Gallop43. Because many users buy an LCD to go with their Gallop43, we will begin with a tour of the buttons found on the right side of the LCD surface of the board, which is the surface you will normally see if you use the LCD a lot. Also shown in this photo are the connectors populating the right edge of Overo COM side of the board -- that is, what connectors are on the other side of those user buttons.

Corner Holes

The holes on each corner of the Gallop43 appear to be sized for 2-56 screws. Screws and nuts of this size tend to loosen easily without locking washers.

User Buttons

The buttons are marked, from top to bottom:

Power On


LED's are marked, from top to bottom:

GPIO21 (D2)
D3 (GPIO22)

The purpose and colors of some of these LEDs are unknown. D10 possibly turns on, glowing red, to indicate the external battery is charging.

Connectors Under User Buttons

When looking at the LCD, one might wonder where a particular connector on the right edge, under the user buttons, is. This section identifies the connectors.

  1. The topmost connector, positioned above the Reset button, is the USB OTG connector.
  2. Directly under the Reset button is the audio connector.
  3. Directly under GPIO21 and (D2) is the USB Console connector.
  4. Directly under D9, D10, and D8 is the external battery connector.
  5. Just under the "Power On" button is the external power (wall wart) connector.

LCD Connector Area

You can click the image on the right to enlarge it and see a view of the LCD connector area. The labeling of IC4 and U$2 are given. Pins 40 (marked "V_IN" on the board and "V_BATT" on website documentation) and 39 ("ADCIN4") of the 40-pin header are located.

Overo COM Side of Board

Now for an examination of the exciting Overo COM side of the Gallop43. Here is where you plug in your Overo and gain access to the board's special features.

U-Blox GPS Details

With the white silkscreen printing on the board "right side up" and readable, the U-Blox module and its MCX antenna connector is tucked into the top right corner of the Gallop43. In this photo, you can see that a U-Blox GPS antenna cable is seated into the gold-colored MCX antenna connector. The cable connector on the antenna sold by U-blox seats quite snugly into the board's connector. It is high quality, as is the Gallop43 connector. The result is a cable that is fairly stiff at the connector end. There is about 2 inches of very noticeable stiffness, then the cable becomes more flexible. This may or may not make a difference to your cable routing. To the right of the MCX connector is a hex aluminum standoff. This is user-supplied and does not come with the purchase of the Gallop43 board. The circled area on the board is quite interesting -- does documentation exist for how to use GPS_V_BCKP? Also of interest is the scannable bar code on the U-blox module's label.

U-blox GPS Antenna

This antenna has a quite long cable of approximately 10 feet in length. The magnetic mount is very convenient to use. The author put the antenna unit magnetic mount side down on an empty tin used for tea samples, and wedged the tin and antenna onto the crank of a window. This was enough for the antenna to pick up satellites and reporting information via the cgps utility. To the left of the antenna, in this photo, an American quarter coin is shown to provide scale.

Connectors for NiMH Battery pack

1/ Connector provided on Gallop43 for NiMH battery pack: - Molex 5268 series #22-05-7025

2/ Mating connector required on NiMH battery pack: - Molex 5264 series #50-37-5023

Coin Cell and NiMH Batteries

Coin cell and NiMH battery solutions have been posted here.