Honeywell HC900 - Manual (Page 19)

Modbus Double Register Format
IEEE Floating Point Formats
Revision 10 HC900 Hybrid Controller Communications User Guide 11
12/07
3.1 IEEE Floating Point Formats
S E7 E6 E5 E4 E3 E2 E1
E0 M22 M21M20 M19 M18 M17 M16
REGISTER N
(High) REGISTER N+1
(Low)
M15 M14 M13 M12 M11 M10 M9 M8
M7 M6 M5 M4 M3 M2 M1 M0
High Low High Low
Bit 0
Bit 31
FP B - Floating Point Big Endian Format:
S=Sign E=Exponent M=Mantissa
S E7 E6 E5 E4 E3 E2 E1
E0 M22 M21M20 M19 M18 M17 M16
REGISTER N
(High) REGISTER N+1
(Low)
M15 M14 M13 M12 M11 M10 M9 M8
M7 M6 M5 M4 M3 M2 M1 M0
High Low High Low
Bit 8
FP BB - Floating Point Big Endian with Byte Swapped Format:
S=Sign E=Exponent M=Mantissa
Bit 31 Bit 24
Bit 23 Bit 16 Bit 7 Bit 0
Bit 15
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