Question about Bitest and Bitest ??

[Nader Belal]

Hi there,

Can someone put a practical example for the use of BITEST & BITSET ?

*Cause I have always seen them being mentioned in GDL manual but never an example that explains how to use them.

[Jochen Suehlo · Accepted solution]

The masking and status values of some other GDL commands are based on set and unset bits of their binary notation. These functions can be analyzed in binary form.
Example: You have a masking Value of 63, which is 1*1 + 1*2 + 1*4 + 1*8 + 1*16 + 1*32
With Bittest you can check, which of these Bits are set or you can check if one of the Bits is set.
val = 63
TEXT2 0, 0, BITTEST(val, 4) ! = 1
This checks, if the 5th value is set (the value 16); the 1st value (1) is on position 0,
so you have to check
TEXT2 0, 0, BITTEST(val, 0) ! = 1
The binary notation of 63 would be 111111 (this is identical with the italic written 1s above), of 64 would be 1000000

[Nader Belal]

Thank you Joachim Suehlo