Oh... now that makes sense.

So I changed the code accordingly as follows

my $data_ref = pack ('U0C*', (0x81 , 0x55, 0x00, 0xE0));

But still end up with the same problem

Maybe its worth the mention that I use Strawberry Perl 5.24.0 (32Bit) on a Win7 64 Bit Machine (since the DLL provided by the manufacturer is a 32 Bit DLL). Could this lead to problems with the array reference?

In reply to Re^2: How to pass a pointer to an array of 'unsigned char' C data type with Win32::API ("U0") by apeks_okad
in thread How to pass a pointer to an array of 'unsigned char' C data type with Win32::API by apeks_okad

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