ICS 8099, Инструкция по эксплуатации

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3-19
3
RR[?] reg, num Read Input Register Command (code 0x04). Reads
one or multiple Modbus device registers. User speci-
fies starting register reg and number of registers to
be read num . The [?] is an optional symbol for smart
programs.
(4)
Values for reg are 0 to 65535. Values
for num are 1 to 64. Responses are returned as 16-
bit decimal or HEX values separated by commas.
Output format selected with the Format command.
See the R? query above.
RE[?] Read Exception Status Query (code 0x07). Reads
eight exception status outputs from a remote device.
The [?] is an optional symbol for smart programs.
(4)
Responses are returned as a packed binary value with
the eight status bits in one byte.
RF? reg Read Floating Point Value Command (code 0x03).
Reads two sequential registers as an IEEE-754 32-bit
floating point value in low byte to high byte order.
The specified register contains the lower two bytes
and the next higher register contains the upper two
bytes.
WC reg, b Write Coil Command* (code 0x05). Writes a ON/
OFF value, b to a single Modbus device register,
reg . Values for reg are 0 to 65535. Values for b
are 0/OFF or 1/ON/255. An example is: WC 1000,
ON
W reg, w Write Register Command (code 0x06). Writes a 16-
bit value, w to a single Modbus device register, reg .
Values for reg are 0 to 65535. Values for w are 0
to 65535. An example is:
W 100, 55 writes the decimal 55 to register 100.
WB reg, num, w(0),.w(n) Write Block Command (code 0x10). Writes multiple
16-bit words, w(i ) to multiple registers or 32-bit
values to two adjacent registers. Starting register,
reg . Number, num specifies how many words are
to be written. Values for reg are 0 to 65535.
Values for nu are 1 to 64. Values for w are 0 to
65535. w(i) values are separated by commas.
TABLE 3-5 MODBUS COMMANDS CONT'D
Syntax Meaning