Easy - use the bitwise and operator (Bitwise And):

use strict;
use warnings;

for my $pattern (0xffd1, 0x0060, 0x0040, 1 << 6, 0xff8f) {
    if ($pattern & (1 << 6)) {
        printf "Bit 6 set in %04x\n", $pattern;
    } else {
        printf "Bit 6 not set in %04x\n", $pattern;
    }
}
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Prints:

Bit 6 set in ffd1
Bit 6 set in 0060
Bit 6 set in 0040
Bit 6 set in 0040
Bit 6 not set in ff8f
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