If I write a task that creates a square wave on the pins of port 8B, all is well.
If I then declare a global variable alongside the original declaration for port 4D, port 8B stops working (see below). This occurs even if I do not reference the 4 bit port variable anywhere in my code.
If I output a (different) square wave to the 4 bit port, this works whether or not the 8 bit port is used. i.e. the 4 bit port takes precedence.
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on tile : out port toggle_port = XS1_PORT_8B; on tile : out port toggle_port2 = XS1_PORT_4D;
Since that is not the case, is the behaviour of this circumstance documented anywhere? Is there any way of catching this kind of error at build time? [I know I can just map out the pins and check, but having a compiler catch errors is always helpful].
n.b. I was checking all of this to test for conflicts with USB PHY. I had written some code that used the four bit port that conflicts with the 8 bit port used by the USB. It built but did not work. Using the actual 8 bit port used does not build (which is nicer).