10F222 ADRES as one more VAR?

[Jerson]

I would look at the LST file to see which variables PBP is not using; just allocating. Let me explain

If you look at pause or maybe pauseus, you will see that PBP uses the R0 and R1 registers each WORD type to handle the delay function. Similarly, PBP uses variables T1 to T4 for Boolean arithmetic (I deduced this by looking at the lst file). You can salvage some RAM by breaking up logical ANDs to a nested if structure - something like this

     ' typical logical and
     if  testcondition1 and testcondition2 then
             do something
     endif

     ' typical logical or
     if testcondition3 or testcondition4 then
             do somethingelse
     endif

can be changed to

     ' simplified logical and
     if testcondition1 then
          if testcondition2 then
                do something
          endif
     endif

     ' simplified logical OR
     if testcondition3 then dosomethingelse
     if testcondition4 then dosomethingelse

the second structure does not involve the T1..T4 variables of PBP and is resource friendly.

Hopefully not using the logical operations of PBP will let PBP yeild the T1 to T4 registers???

A look into the Listing file will yeild some more. I haven't gone into the details yet.

[JetPack Spartan]

Okay, I guess that explains why I couldn't get my program working, would have been nice to use ADRES.

As far as the booleans, I cannot use them now without getting the "unable to fit variable" error.

I currently use one word sized and one byte sized variable.

When I look at the list file I see that R2 and R3 are not used. Does that mean I can do something like;

NewVariable  VAR   R2

New approach, I set OPTION_REG.5 = 1 so that TMR0 would not increment and I am using that for my missing byte. It is working so far... but if I can use R2 or R3 that would be better because I wanted to try to use TMR0.

Rich H

[Jerson]

Looks like you can get by doing that. Try it out!!!

[Bruce]

With Timer0 clock source set to external, and using TMR0 register as a variable, I would check to make sure TMR0 isn't incrementing when taking GP2 high/low.

Some internal counters, when configured for external clocks, will increment if you're using the pin as an output & toggling the pin.