KROHNE MFC 010 C Converter - Manual (Page 96)

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MFC010 Interface Manual
Therefore = -1 0 x 2 (144-127) x [1 + { 4806344 / 2 23 }] = 1 x 2 17 x 1.5729609 = 206171.131
NB Accuracy up to the seventh digit i.e. 206171.1
Double Precision Floating Point Numbers (“Doubles”)
Double precision floating-point values are coded in a gr oup of 8 by tes (64 bits, as shown below). T his
enables the computer to represent values over a r ange of ±1.7 x 10 ±308 , with an ac curacy of 15 dec imal
digits.
S E E E E E E E E E E E M M M M M M M M M M M M M M M M M M M M
Byte 7 (MSB) Byte 6 Byte 5 Byte 4
M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M
Byte 3 Byte 2 Byte 1 Byte 0 (LSB)
To encode a value into a double precision floating point representation, use the following process.
Step 1 : If Value < 0 (i.e. negative) S = 1, otherwise S = 0
Step 2 : Set E = 1023
Step 3 : If Value < 2, skip to step 6
Step 4 : Divide the Value by 2, add 1 to E
Step 5 : Go back to step 3
Step 6 : If Value > 1, skip to step 9
Step 7 : Multiply the Value by 2, subtract 1 from E
Step 8 : Go back to step 6
Step 9 : M = ( Value – 1 ) * 2 52
To decode a double precision floating point representation use the following formula.
Floating Point Value = -1 S x 2 (E-1023) x [ 1 + { M / 2 52 } ]