ICS 8099, Инструкция по эксплуатации

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3.6 MODBUS COMMANDS
The following commands are used to Control Modbus slave devices. These
Modbus Commands should not be mixed or concatenated with IEEE-488.2 or
SCPI commands.
TABLE 3-5 MODBUS COMMANDS
Syntax Meaning
C addr Modbus Address Command. Sets Modbus slave
device address for subsequent commands. Value
for addr is 1 to 255. Default setting is 1.
RC[?] reg, ncoil Read Coil Status Command (code 0x01). Reads the
status of coils in a remote device. User specifies start-
ing coil address in register reg and number of coils to
be read ncoil . The [?] is an optional symbol for smart
programs.
(4)
Values for reg are 0 to 65535. Values
for ninp are 1 to 2000. Responses are returned as a
packed binary value with 1 bit per coil. 1 = ON.
RI[?] reg, ninp Read Discrete Inputs Command (code 0x02). Reads
discrete inputs. User specifies starting address in
register reg and number of inputs to be read ninp .
The [?] is an optional symbol for smart programs.
(4)
Values for reg are 0 to 65535. Values for ninp are 1
to 2000. Responses are returned as a packed binary
value with 8 inputs per byte. 1 = ON.
R[?] reg, num Read Register Command (code 0x03). 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 16-
bit decimal or HEX values separated by commas.
Output format selected with the Format command.
i.e.
R? 0,1 reads Watlow Model Number. Response is
5270 for Watlow Model F4
R? 0,3 reads three successive registers. Response is
5270,0,123 for the Watlow F4 Controller.