Subtracting contents of a BYTE

Oldbitcollector (Jeff)

How do I subtract a number from a byte variable?

I've got some code that is case sensitive, so I need to decrease the contents of the byte by 32
to change case. Is there an easy way to do this instead of a lookup table?


Example if "@byte:=97" I need it to equal 65 (lower to upper)

Thanks
OBC

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CardboardGuru

I'm not sure what you mean by @byte:=97. That's not valid spin.

But to subtract from a byte variable "b" use b-=32

If you have a pointer to a byte "p", use byte[noparse][[/noparse]p]-=32

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Phil Pilgrim (PhiPi)

Try this:

if (ch => "a" AND ch =< "z") 
  ch -= 32

-Phil

Mike Green

You subtract a number from a byte variable just like you'd do it with any
other variable: "variable := variable - 32" or "variable -= 32".
If what you have is an address, you'd use "byte[noparse][[/noparse] <address> ] -= 32".

You could do: "variable := ((variable > $5F) & $20) ^ variable".
It always converts lower case characters (anything from $60 to $7F)
to upper case characters (from $40 to $5F).

Oldbitcollector (Jeff)

I was stuck; missing the = sign.

Working perfectly -- Thanks!

OBC

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Buttons . . . check. Dials . . . check. Switches . . . check. Little colored lights . . . check.

— Calvin, of 'Calvin and Hobbes.