BCD List to HEX List

[Philippe Martin]

John Machin wrote:

> Philippe Martin wrote:
>> Hi,
>>
>> I'm looking for an algo that would convert a list such as:
> 
> Such as what?
> 
>>
>> I'm using python to prototype the algo: this will move to C in an
>> embedded system where an int has 16 bits - I do not wish to use any
>> python library.
>>
>> l1 = [1,2,3,4,6,7,8] #represents the decimal number 12345678
> 
> Does it??? How do you represent the decimal number 12349678, then?
> 
>> l2 = func (l1)
>> # l2 = [0x1, 0x2, 0xD, 0x6, 0x8, 0x7] #represents 0x12D687
>>
> 
> I'm sorry, but very little of that makes any sense to me:
> 
> 1. I thought BCD meant something very much like this:
> http://en.wikipedia.org/wiki/Binary-coded_decimal
> 
> 2. >>> [0x1, 0x2, 0xD, 0x6, 0x8, 0x7] #represents 0x12D687
> [1, 2, 13, 6, 8, 7]
> 
> So [1], [2], [6] are unchanged, [3, 4] -> [13] (or maybe [3, 4, 5] ->
> 13),  and [7, 8] -> [8,7].
> 
> I doubt very much that there's an algorithm to do that. What is the
> relationship between 1234(maybe 5)678 and 0x12D687??? I would expect
> something like this::
> 
>     0x12345678 (stored in 4 bytes 0x12, ..., 0x78)  -- or 0x21436587
> or
>     0x012345678s (where s is a "sign" nibble; stored in 5 bytes 0x01,
> ..., 0x8s)
> 
> IOW something regular and explicable ...
> 
> 3. Perhaps it might be a good idea if you told us what the *real*
> problem is, including *exact* quotes from the manual for the embedded
> system. You evidently need/want to convert from one representation of
> signed? unsigned? integers to another. Once we all understand *what*
> those representations are, *then* we can undoubtedly help you with
> pseudocode in the form of Python code manipulating lists or whatever.
> 
> Cheers,
> John


Hi,

>From my answer to Marc:

>My apologies, I clearly made a mistake with my calculator, yes the
>resulting
>array I would need is [0xb,0xc,0x6,0x1,0x4,0xe]



Philippe