#define to a pin and testing to a variable

Jim McBride · Joined: 24 Mar 2004 Posts: 21

I have not been able to search out and answer in the list.
I have defines set to input pins. But when I try and test on those against int sized variables the results are not what I expect. Is my problem testing a bit against a byte even if the byte is a 1 or 0? Do I have to make a bit variable for testing? Am I being grossly ignorant?

#define Trig_source PIN_D0
int internal = 1;

if(Trig_source == internal)
run_internal();

When PIN_D0 is set high(simulated), the IF statement will never test true.
Thanks,
JIMc

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

Use the input() function to read the pin. Then test the value
returned by that function.

Jim McBride · Joined: 24 Mar 2004 Posts: 21

OK will do. The #define seems to work fine for outputs. Not sure why I was expecting a variable to automatically grab an input from a port. wishful thinking...
Wanting to keep the code readable, the following works fine:

#define Trig_source PIN_D0
int internal = 1, external = 0;

if( input(Trig_source) == internal )
run_internal();

Thanks for the help!!