Question about Constants / Variables in Spin

[CassLan]

Hi all,

If I define a constant as the sum of two variables:


CON
VARSUM = VAROne + VARTwo

VAR

Byte VAROne, VARTwo
As I change the values of VAROne and VARTwo, will the value of VARSUM change automatically?
Or would I have to make VARSUM a variable and update its value as VAROne and VARTwo change?

I would test this but am not near a setup right now, and am making some outlines for a program.

Thanks,

Rick

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[Oldbitcollector (Jeff)]

I don't have my prop hooked up, but it doesn't compile...

OBC

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[jazzed]

CassLan said...
As I change the values of VAROne and VARTwo, will the value of VARSUM change automatically?
Or would I have to make VARSUM a variable and update its value as VAROne and VARTwo change?


A constant can only change at compile time. Be thankful that the example does not compile :)

[Luis Digital]

The operations in the "CON" section are performed by the Propeller IDE (compile time) no Propeller Chip (run time).

CON
VARSUM = VAROne + VARTwo

It is simply a reference, something easy to remember.

[potatohead]

Constants are computed at compile time.

If you calculate something with a constant, then use that constant in your program, the value result of the calculation will be put into the program just as if you had typed it in.

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[CassLan]

WOW, talk about fast responses!

Ok, I see, at compile time it replaces chunks of my program with the appropriate values for the constants, its merely a human aid in writing the software.

Thanks!

Rick

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