ICS ELECTRONICS 4809A, Инструкция по эксплуатации, Страница: 72 / 131

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RR[?] reg, num * Read Input Register Command (code 0x04). Reads one
or multiple Modbus device registers. User specifies
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 signed 16-bit decimal or
HEX values, +32767 to -32767, 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, reg , 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 +32767 to
-32767. 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 . Values
for reg are 0 to 65535. Number, num specifies how
many words are to be written. Values for num are 1 to
64. Values for w are +32767 to -32767. w(i) values
are separated by commas.
TABLE 3-5 MODBUS COMMANDS CONT'D
Syntax Meaning