>>Hit to 'the other purpose' :) Well I simply do :
>
>Right!
>
>>lnNumber1 = iif(lnNumber > 0x7FFFFFFF, 0x7FFFFFFF-lnNumber, lnNumber)
>
>What I needed was that:
>

 number 0 translates to chr(0) 0x00 (not 0x80)
> number 1 translates to chr(1) 0x01 (not 0x81)
> ...
> number 208142404 to chr(12)+chr(104)+chr(0)+chr(68) 0x0C680044
>                (not chr(140)+chr(104)+chr(0)+chr(68) 0x8C680044)
>

>
>It's a very simple UDF to get that, but bintoc() would have been even simpler.
>
>Thanks again.

You mean like:

transform(208142404,"@0") returns 0x0C680044