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 # passerelleLoRa
 Projet BTS SNIR 2ème année
 Gateway between a weather MicroStation using LoRa modulation and a web server. This depo is segmented in different programs for arduino using ATMEGA328P and SAMD21.
+
+#Attention !
+Because we're using two arduino shields using SPI communication, we need to select a chip select for each shield. I decided to use D11 for the Ethernet shield (10 for the LoRa, 4 for the SD).
+
+To do this, edit w5100.h in the default ethernet librairy in the installation folder of your arduino IDE (on windows, in adminisstrator mode ‪C:\Program Files (x86)\Arduino\libraries\Ethernet\src\utility\w5100.h).