BeagleBone I/O pins
The operating system image that comes with this book is supposed to work on either the BeagleBone White board or the newer BeagleBone Black board. The Black board uses some of the I/O for the LCD display and the eMMC chip, thus, in order to make the system hardware work with either version, we must take care not to use any of the I/O used by the Black board.
The following table shows the I/O pins common to both boards.
P9 |
P8 | ||||
---|---|---|---|---|---|
GPIO |
Pin # |
Signal |
GPIO |
Pin # |
Signal |
N/A |
1 |
Gnd |
45 |
11 |
1 dB |
2 |
Gnd |
44 |
12 |
2 dB | |
3 |
VDD_3V3 |
23 |
13 | ||
4 |
VDD_3V3 |
26 |
14 |
4 dB | |
43 |
Gnd |
47 |
8 dB | ||
44 |
Gnd |
46 |
16 |
0.5 dB | |
45,46 |
Gnd |
27 |
17 |
LE |
The attenuator is connected directly to the I/O pins of the BeagleBone, and attenuator power comes from the BeagleBone. The attenuator has only inputs, so power sequencing cannot damage the BeagleBone I/O pins.
The signals are brought out to an eight-pin male connector that mates with a female connector installed on the cable...