Randy Yates wrote:
> thunder <[email protected]> writes:
>
>> Hi
>>
>> I have a question regarding Fixed point Arithmetic addition.
>>
>> For example, i have two fixed point numbers:
>>
>> a = unsigned Q7.8 format (7-bit integer, 8 bit factional).
>> b = unsigned Q7.8 format ( " " ).
>>
>> Now a + b = c, where c is an unsigned Q8.8 result.
>>
>> Qs: How do I transform c into d, where d is a unsigned Q7.9 result ??
>
> There is no way in general to do this conversion and avoid some kind of
> nonlinear effect since the range of Q7.9 is smaller than Q8.8. The most
> obvious method would be to saturate the Q8.8 result to Q7.9.
>
> It would be good to know the reason why you're trying to rescale in this
> manner - there may be a better way to do things from a higher level
> point-of-view.

I suggest that the give thunder time to glean an understanding from your
monograph, then ask for whatever further clarification he still needs.

Jerry
--
Engineering is the art of making what you want from things you can get.
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