Got it working on port 9
I've added this at the top:
define LED_BUILTIN 9
And this is the warning that you get if you set the compiler warnings to ALL in preferences.
C:\Users\sterretje\AppData\Local\Temp\arduino_modified_sketch_594459\sketch_mar07a.ino:1:0: warning: "LED_BUILTIN" redefined
#define LED_BUILTIN 9
In file included from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Arduino.h:257:0,
C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\standard/pins_arduino.h:54:0: note: this is the location of the previous definition
#define LED_BUILTIN 13
Understand what you are doing. You should not redefine a predefined pin. How would you have added a second led (on pin 9)?
#define OTHERLED 9
And in setup() you would have used something like
And to control the led, you would have used e.g.
Now find a decent name for OTHERLED and you're good to go.
With regards to your original problem, your shield uses the SPI bus and pin 13 is the SPI clock. Pin 13 is also the built-in led and hence you have a conflict.