Hardware Reference
In-Depth Information
Table 4-2.
Cacheberry LCD pin mapping
CACHEBERRY LCD PIN LABEL
RASPBERRY PI BCM GPIO PIN
GND
GND
SCL
3 (SCL)
SDA
2 (SDA)
VCC
5 V
If you want to connect an indicator LED, wire it into BCM Pin 25 (P1-22), with an ap-
propriate resistor between the BCM 25 pin and the positive leg of the LED. The type
of resistor will depend on the specifications of the LED being used. For example, if you
use a Red LED with a voltage of 2 V and a current of 15 mA, the 5 V circuit will require
a 220 ohm resistor. You can calculate the resistor value for your LED with this website:
http://led.linear1.org/1led.wiz
The negative leg of the LED should wire to an available
GPIO ground (GND) pin.
Connect the Raspberry Pi to the mini-USB power cable (fed from the 12 V cigarette
lighter receptacle), and the OS image should boot up.
Loading Cache Data
Because the Cacheberry Pi is not networked, you need to load geocaches via a USB
flash drive. It is configured to always listen for a USB drive to be inserted, and when
one is inserted with the proper filesystem layout, it will automatically import the
geocache database off of the USB drive. It will also copy the track history from the
Cacheberry Pi to the USB flash drive.
To set up a USB flash drive, insert it into your Linux computer and make sure it is
mounted. Most Linux distributions will automount USB storage devices when they are
inserted. Check the output of the
mount
command for a
/dev/sdb
or
/dev/sdc
device
(
/dev/sda
is usually the laptop hard drive), and then change into the directory where
the USB drive is mounted.
Download and decompress the “sample” ZIP file for the Cacheberry USB filesystem
layout. Then copy the files into the mounted USB drive (in this example, we assume
it is mounted at
/mnt/usbdrive
):
$ cd ~
$ wget http://cdn.jclement.ca/cacheberrypi/cacheberrypi_usbstick_sample.zip
$ unzip cacheberrypi_usbstick_sample.zip
$ cp -a cacheberrypi_usbstick_sample/* /mnt/usbdrive
The USB drive is now prepared for use, but you'll want to add some cache entries. The
Cacheberry Pi will look for a file named
nav.csv
in the
cacheberrypi/
directory. This
