[bootlin/training-materials updates] master: labs/sysdev-u-boot-stm32: explain why there is nothing on the console at the begining (57b6341a)

[Michael Opdenacker]

Repository : https://github.com/bootlin/training-materials
On branch  : master
Link       : https://github.com/bootlin/training-materials/commit/57b6341af49406c1b25c989b7d72c1ec0ae4706c

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commit 57b6341af49406c1b25c989b7d72c1ec0ae4706c
Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
Date:   Mon Sep 26 16:38:53 2022 +0200

    labs/sysdev-u-boot-stm32: explain why there is nothing on the console at the begining
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>


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57b6341af49406c1b25c989b7d72c1ec0ae4706c
 labs/sysdev-u-boot-stm32/sysdev-u-boot-stm32.tex | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/labs/sysdev-u-boot-stm32/sysdev-u-boot-stm32.tex b/labs/sysdev-u-boot-stm32/sysdev-u-boot-stm32.tex
index 4373e071..e9f1bf44 100644
--- a/labs/sysdev-u-boot-stm32/sysdev-u-boot-stm32.tex
+++ b/labs/sysdev-u-boot-stm32/sysdev-u-boot-stm32.tex
@@ -61,6 +61,10 @@ You have to run it in each terminal.
 Run \inlinebash{$ picocom -b 115200 /dev/ttyACM0}, to start serial
 communication on \code{/dev/ttyACM0}, with a baudrate of 115200.
 
+Don't be surprised if you don't get anything on the serial console yet,
+even if you reset the board. That's because the SoC has nothing to boot
+on yet. We will prepare a micro SD card to boot on in the next paragraphs.
+
 If you wish to exit \code{picocom}, press \code{[Ctrl][a]} followed by
 \code{[Ctrl][x]}.