From 8c7749547a0331c198e0bc050066c53e52e91135 Mon Sep 17 00:00:00 2001
From: Florian Kaltenberger <florian.kaltenberger@eurecom.fr>
Date: Wed, 8 Sep 2021 13:48:40 +0000
Subject: [PATCH] Update BUILD.md

---
 doc/BUILD.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/BUILD.md b/doc/BUILD.md
index bbb06a1e698..166563877ef 100644
--- a/doc/BUILD.md
+++ b/doc/BUILD.md
@@ -77,7 +77,7 @@ cd cmake_targets/
 ./build_oai -I -w USRP --eNB --UE --nrUE --gNB
 ```
 
-- The `-I` option is to install pre-requisites, you only need it the first time you build the softmodem or when some oai dependencies have changed. 
+- The `-I` option is to install pre-requisites, you only need it the first time you build the softmodem or when some oai dependencies have changed. Note: for Ubuntu 20 use cmake_targets/install_external_packages.ubuntu20 instead!
 - The `-w` option is to select the radio head support you want to include in your build. Radio head support is provided via a shared library, which is called the "oai device" The build script creates a soft link from `liboai_device.so` to the true device which will be used at run-time (here the USRP one,`liboai_usrpdevif.so` . USRP is the only hardware tested today in the Continuous Integration process. The RF simulator[RF simulator](../targets/ARCH/rfsimulator/README.md) is implemented as a specific device replacing RF hardware, it can be specifically built using `-w SIMU` option, but is also built during any softmodem build.
 - `--eNB` is to build the `lte-softmodem` executable and all required shared libraries
 - `--gNB` is to build the `nr-softmodem` executable and all required shared libraries
-- 
GitLab