XOR and OR calculations in IL - surprising results

FAQ #100720

You may wonder about surprising results when programming in IL with XOR and OR operations.

It's good to know the philosophy behind.


IL-programmer will wonder why the ANL of flag 2 operation in the below picture will result in a high accu state.


One have to understand that XOR and OR operations work like "open paranthesis" for arithmetic calculation.
If you want to apply the result of the XOR and OR operation, one have to "close paranthesis" by programming
an OUT on a dummy flag and testing the state of this flag by a STH as shown in the example below. Now, the
ANL of flag 2 operation results in a low accu state.






Local FAQ Deutschland / SEdit (IL programming)

Last update: 28.05.2015 12:53

First release: 07.06.2007 13:04

Views: 1342

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