Rev. 1.00
22586_EDEBD
A0253-0318-1_EN
51
KBR multicomp F144-3 6DO/6RO
13.1
Modbus commands supported
0x04
Read input registers
0x2B
Read device identification
The multicomp F144-3 does not support broadcast commands. All Modbus
commands described are device-specific commands.
13.2
Data formats
(unsigned) short: 0x1234
Address
+0
+1
Contents
0x12
0x34
Rule for byte sequence: MSB before LSB
(unsigned) long: 0x12345678
Address
+0
+1
+2
+3
Contents
0x12
0x34
0x56
0x78
Rule for byte sequence: MSB before LSB
float:
Format
Complies with the IEEE 754 standard
Representation
4 bytes
Accuracy
24 bits ( represent >7 decimal points)
Composition
24-bit mantissa; 8-bit exponent
Mantissa
24 bits (M) + 1 bit (S)
Exponent
The MSB of the mantissa is always 1 => it is not saved
separately! S = sign of the mantissa: S = 1 negative
number; S = 0 positive number
Exponent
8 bits (0-255); is saved relative to 127, i.e. the current
value of the exponent is calculated by subtracting the
number 127 from the saved value.
Curr. exp. = saved exp value. – 127
=> range from 128 to -127!
