ProSoft Technology 5201-DFNT-104S User Manual
Page 60
104S v2 ♦ ProLinx Gateway
IEC-60870-5-104 (104S) Protocol Implementation
(Firmware v2.xx)
Protocol Manual
Page 60 of 157
ProSoft Technology, Inc.
March 19, 2010
Monitored Measured Normalized points use a data representation defined by the
protocol specification to represent fractional decimal values. The following table
describes the value for each bit as a reciprocal power of two (2), that is two (2)
raised to the power of a negative exponent ( -1 through -15). Bit 15 is the Sign
Bit.
Bit 15 14 13 12 11
10 9 8 7 6 5 4 3 2 1 0
Value
Hex
Decima
l
S 2
-1
2
-2
2
-3
2
-4
2
-5
2
-6
2
-7
2
-8
2
-9
2
-10
2
-11
2
-12
2
-13
2
-14
2
-15
4000h
0.5
0
1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
2000h
0.25
0
0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
1000h
0.125
0
0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
6000h
0.75
0
1 1 0 0 0 0 0 0 0 0 0 0 0 0 0
3210h
0.3957
519531
25
0
0 1 1 0 0 1 0 1 0 1 0 1 0 0 0
Examples:
A value of 4000hex (only Bit 14 set, all others clear) is interpreted as 0.5 decimal
A value of 2000hex (only Bit 13 set, all others clear) is interpreted as 0.25
decimal
A value of 1000hex (only Bit 12 set, all others clear) is interpreted as 0.125
decimal
... and so on until...
A value of 0001hex (Only Bit 0 set, all others clear) is interpreted as
0.000030517578125
Therefore, the actual data values transmitted may be any combination of the
decimal values for any given bit pattern.