View source for RRU Setup Raspberry PI

<span id="set-up-the-raspberry-pi-4"></span>
== Set up the Raspberry Pi 4: ==

<span id="configure-the-internal-serial-port"></span>
=== Configure the internal serial port: ===

Add user to dialout group:

<pre>sudo usermod -aG dialout $USER
newgrp dialout # or log off / log in</pre>
Disable serial console:

<pre>sudo systemctl stop serial-getty@ttyS0.service
sudo systemctl disable serial-getty@ttyS0.service</pre>
Set overlay: This moves <code>/dev/ttyAMA0</code> to where the UART RX/TX pins are located (GPIO14/15).

<pre># Backup the config file
sudo cp /boot/firmware/config.txt /boot/firmware/config.txt.bak
sudo sh -c &quot;echo 'dtoverlay=miniuart-bt' &gt;&gt; /boot/firmware/config.txt&quot;</pre>
Enable UART:

<pre>sudo raspi-config
# Select &quot;Interface Options&quot; &gt; &quot;Serial Port&quot; to enable UART
# Login Shell -&gt; No
# Hardware -&gt; Yes
# Reboot</pre>
Check if the serial port is present:

<pre>ls -hal /dev/ttyAMA0</pre>
This should return something like:

<pre>oe3anc@rru:~ $ ls -hal /dev/ttyAMA0    
crw-rw---- 1 root dialout 204, 64 Apr 25 10:12 /dev/ttyAMA0</pre>
<span id="connecting-the-raspberry-pi-to-the-rru"></span>
=== Connecting the Raspberry Pi to the RRU ===

On the Pi 4, I used these pins:

{| class="wikitable"
|-
! Pi 4
! RRU
|-
| 14
| TX
|-
| 15
| RX
|-
| 17
| NRST
|-
| 27
| PA
|-
| GND
| GND
|}
A good overview of the pinout: https://pinout.xyz/