Incon 1250B, Инструкция по установке и программированию, Страница: 27 / 36

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In the following Table 3.8, the meanings of the columns are as follows:
Register:
MODBUS register address as seen in a MODBUS command beginning with
register 40001 and ending with 49220. These addresses are in
decimal .
Hex:
The same register’s address in
hexadecimal , this value is calculated by
subtracting 40001 from the register number. Thus register 40001 in decimal
becomes 0000 in hex, and 40257 in decimal becomes 0100 in hex.
Function:
Defines what each register contains or does when written. Some registers
are read only and have no meaning when written. Others can be written
or read. Others are write only special function and cause actions to be
performed when they are written. Still others are “select registers”, which
select what other registers do when they are read or written. 45890 (1701h) is
such a register, and selects which table position is affected by the other
registers.
Format:
This column defines what a register contains bit-by-bit in binary . A row of 16
symbols shows what each of the 16 bits of the register contain MSB first
and LSB last. A BCD formatted floating point register is shown as
follows (two 16 bit binary words):
Bcdabcdbbcdcbcdd bcde000000vspppp
bcda, bcdb, bcdc, bcdd, bcde are each four-bit BCD digits, as it
would be seen on a display.
000000 are 6 unused bits that report as 0 when read and must be 0
when written.
v is an overflow bit that indicates that the number in the register is too
big to display when it is a 1. 0 indicates a valid register value.
s is the sign bit and is 1 when the value in the register is negative. 0
indicates a positive number.
pppp is the position of the decimal point within the bcd digits.
Most registers are not as complex as a floating-point register.
An alternate floating-point format is supported and selected by writing a 1 to
the 40256d (
00ff h ) register. This selects an IEEE floating-point format as
follows (two 16 bit binary words):
seeeeeeeemmmmmmm mmmmmmmmmmmmmmmm
The format of the IEEE floating-point number is as follows:
s is the sign bit,
e is the exponent bits, and
m are the mantissa bits.