Yaskawa Remote Serial Communication Controller LAN Node PCB for use with Microtrac DSD LAN - Manual (Page 15)

The LOGIC MASK contains the error states for each of 32 subchannels. The error state of
Subchannel 0 is the state of the least significant bit (D0) of the lsb of LOGIC MASK (at offset 6). The
error state of Subchannel 31 is the state of the most significant bit (D7) of the msb of LOGIC MASK (at
offset 3). Bits set to logic 1 in the LOGIC MASK are in error.
IEEE Single Precision Floating Point Format. Numeric values passed in the messages are in the
number format set by the IEEE 754 single precision floating point standard. Its bit form representation is
as follows:
SEEE EEEE EMMM MMMM MMMM MMMM
MMMM MMMM
Most Significant
Byte (MSB) Least Significant
Byte (LSB)
"S" is the sign bit (1 if negative, 0 if positive). The "E" field is the two's exponent. It is a two's
complement value biased by 127 (decimal). The "M" field is the 23 bit normalized mantissa. The most
significant bit is always assumed to be 1, and so is not explicitly stored. This yields an effective precision
of 24 bits.
The value of the floating point number described above is obtained by multiplying 2 raised to the
power of the unbiased exponent, by the mantissa. The assumed bit of the binary mantissa (the most
significant bit) has a value of 1.0, with the remaining bits providing a fractional value (i.e. the value of the
mantissa is greater than or equal to 1.0 and less than 2.0).
The dynamic range of the IEEE 754 single precision floating point format is +/-1.75494E-38 to
3.402823E+38.
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RD 790-30