diff --git a/demos/STM32/RT-STM32F103-STM3210E_EVAL-FATFS-USB/readme.txt b/demos/STM32/RT-STM32F103-STM3210E_EVAL-FATFS-USB/readme.txt
index 4561b87..3ed13e2 100644
--- a/demos/STM32/RT-STM32F103-STM3210E_EVAL-FATFS-USB/readme.txt
+++ b/demos/STM32/RT-STM32F103-STM3210E_EVAL-FATFS-USB/readme.txt
@@ -17,6 +17,10 @@ commands there.
 The demo has been tested by using the free Codesourcery GCC-based toolchain
 and YAGARTO.
 Just modify the TRGT line in the makefile in order to use different GCC ports.
+
+If the compilation has trouble finding "diskio.h" or "ff.h" you need to 
+go to ../../../ext and unpack the (patched) fatfs archive. 
+
 
 ** Notes **
 
diff --git a/demos/STM32/RT-STM32F407-OLIMEX_E407-LWIP-FATFS-USB/readme.txt b/demos/STM32/RT-STM32F407-OLIMEX_E407-LWIP-FATFS-USB/readme.txt
index c3a361a..1d6865d 100644
--- a/demos/STM32/RT-STM32F407-OLIMEX_E407-LWIP-FATFS-USB/readme.txt
+++ b/demos/STM32/RT-STM32F407-OLIMEX_E407-LWIP-FATFS-USB/readme.txt
@@ -20,6 +20,10 @@ The demo has been tested by using the free Codesourcery GCC-based toolchain
 and YAGARTO.
 Just modify the TRGT line in the makefile in order to use different GCC ports.
 
+If the compilation has trouble finding "diskio.h" you need to go to
+../../../ext and unpack the (patched) fatfs archive. The same holds 
+lwip/opt.h which is in the lwip package. 
+
 ** Notes **
 
 Some files used by the demo are not part of ChibiOS/RT but are copyright of
diff --git a/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/main.c b/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/main.c
index 81c5e2f..32fca30 100644
--- a/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/main.c
+++ b/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/main.c
@@ -27,6 +27,7 @@
 #include "lwipthread.h"
 #include "web/web.h"
 
+// From FatFs. See readme.txt if this include is not found. 
 #include "ff.h"
 
 #include "usbcfg.h"
diff --git a/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/readme.txt b/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/readme.txt
index f7cc4c9..2682fe3 100644
--- a/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/readme.txt
+++ b/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/readme.txt
@@ -19,6 +19,11 @@ commands there.
 The demo has been tested by using the free Codesourcery GCC-based toolchain
 and YAGARTO.
 Just modify the TRGT line in the makefile in order to use different GCC ports.
+
+If the compilation has trouble finding "diskio.h" you need to go to
+../../../ext and unpack the (patched) fatfs archive. The same holds
+for the lwip/opt.h include which is in the lwip archive. 
+
 
 ** Notes **