Installing a Raspberry Pi Kit
How to attach a Raspberry Pi Kit
The Open Access v4 comes equipped with a 6-pin header that can directly interface to any Rapsberry Pi computer.
Additionally, mounting holes are provided for attaching the device directly to the Open Access board, making this a clean, compact solution.
Mounting the Pi
- A Rasberry Pi Model B mounts straight to the PCB using the mounting holes at opposite corners of the PCB. 0.750"nylcon spacers and 4-40 nylon screws are provided.
- A Model B+ uses different hardware. The straight spacer goes on the lower left mounting hole, and the offset spacer goes on the upper right.
Header location and pinout
The header is located on the lower left corner of the PCB, next to the Lithium 2032 battery. It is labelled J5/RPi-IN.
Pinouts are as follows:
1 3.3V In
2 +5V Out
4 UART RX
5 UART TX
Raspberry Pi Pinout and connections
The supplied ribbon cable will power the Raspberry Pi, and optionally allow a direct UART interface to between the Open Access and the Pi, saving a USB port. When used in this manner, 2-wya communication is possible, but not software updates. Updating the software on the Open Access requires attaching a USB cable and setting jumper J5 to "USB." Set J5 to RPi to use the on-board UART connection.
Note that the Mode B and Model B+ have different connectors. The older Model B uses a 26-pin 2-row connector, while the newer B+ uses a 40-pin connector. Fortunately, the power, ground and UART pins are in the same place for each. When installing the Raspberry Pi connector, make sure to connect Pin 1 on the Open Access with Pin 1 on the Pi. For reference, here is the RPi GPIO pinout: