my $data = \[ $cmd ];  # Create an array reference for a single comman
+d byte

[download]

should be 

my $data = [ $cmd ];  # Create an array reference for a single command
+ byte

[download]

You were sending a reference to a reference to an array :(

In reply to Re^2: ST7789V2 LCD Controller by tybalt89
in thread ST7789V2 LCD Controller by Bod

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