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Charles Linquist
Joined: 07 May 2005 Posts: 28 Location: Campbell, CA
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Another newbie question |
Posted: Mon May 16, 2005 4:26 pm |
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In the code below
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IF (ToggleCounter1 ^ ToggleCounter2 ^ ToggleCounter3 ^ ToggleCounter4 ^ ToggleCounter5 ^ ToggleCounter6 ^ ToggleCounter7 ^ ToggleCounter8);
{Output_bit(PIN_A0,0);
ELSE
Output_bit(PIN_A0,1)};
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On the ELSE statement, I get an error message "A numeric expression must appear here".
What I'm tring to do is to test if any of the 8 ToggleCounters is TRUE, then set or reset Pin A0.
All of the ToggleCounters are INT1.
I can't figure out what is wrong. Can somebody help me? |
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dyeatman
Joined: 06 Sep 2003 Posts: 1934 Location: Norman, OK
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Posted: Mon May 16, 2005 5:27 pm |
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Syntax problem.
Remove the semi-colon after your expression then remove the curly braces before and after the else.... all you need are the two semicolons, one after each action statement.
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IF (ToggleCounter1 ^ ToggleCounter2 ^ ToggleCounter3 ^ ToggleCounter4 ^ ToggleCounter5 ^ ToggleCounter6 ^ ToggleCounter7 ^ ToggleCounter8)
Output_bit(PIN_A0,0);
ELSE
Output_bit(PIN_A0,1);
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That should work... although I think you might want the logical OR rather than the bitwise OR... |
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iso 9001 Guest
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Posted: Tue May 17, 2005 2:25 am |
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Thats XOR there.
And you could use bitwise OR I think, it should be the same as evaluating out to a bool anyway.
Either way, you probably don't want XOR. |
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Charles Linquist
Joined: 07 May 2005 Posts: 28 Location: Campbell, CA
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Posted: Tue May 17, 2005 6:40 am |
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Thanks! The program compiles now, and I'll switch my operators - which brings up another question, when I have an int1 variable, and I want to AND or OR it, should I use the bitwise operator, or the regular operator, or does it matter? |
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newguy
Joined: 24 Jun 2004 Posts: 1909
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Posted: Tue May 17, 2005 9:42 am |
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Whenever you want to see if something evaluates to "true" - i.e. in an if() or while() loop, you use the double and or double or: && or ||.
&& or || means "see if this is true" - & or | means "do a bitwise and/or". Probably not what you want in an if() or while() loop. |
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