[aprssig] Dear Mr Kenwood (MicE decoding)

[david Vanhorn]

Take the fractional part and use a lookup table.

-- Sent from my Palm Prē
Scott Miller wrote:

> Done.  Plus a little cleanup here and there...  It was designed

> to be a pretty simple manipulation of bits.  A table was never

> intended.  That was just how Ian decided to represent the 
> algorithm in the spec making it appear overly complex when in

> fact, it is a very simple offset of bits.



And how would you suggest implementing the speed and altitude?  Where

speed = (1.08^x)-1 and altitude = 1.002^x?  Yeah, it's easy on a PC

where you've got floating point support and memory and CPU cycles to

burn.  Not fun on an 8-bit MCU that more often than not doesn't even

have a hardware multiplier.  Certainly not as simple as the single

QBASIC statement needed to handle it might imply.



Scott

N1VG





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