On 02/05/2011 14:38, Dave Tweed wrote:
>> >  Is result only up to 999 (three digits)?
> No, the result is three bytes of packed BCD, or 6 decimal digits.
>
>> >  But I don't understand it.
> It's relatively straightforward. The combination of the AdjBcd()* calls a=
nd the
> left shift constitutes multiplying a 3-byte (6-digit) number by two in BC=
D.
> The original sixteen bit number is converted to decimal one bit at a time
> starting with the MSB, by multiplying the BCD result by two and then addi=
ng
> the next bit from the original binary number.
>

Thanks.

I think some 1960s mainframes actually had instructions to do it this=20
way and then libraries for BCD arithmetic for large amounts of money.

JAL has added some features since originally that was written as you can=20
have now arrays and also alias larger types passed as parameter to an=20
array of byte in a procedure.

So a "modern" version of that can just take two parameters. Probably for=20
conversion to String or Multiplexed Displays an "unpacked" BCD array=20
version is good.



--=20
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