Instruction Manual

6. Modbus ASCII
295
Modbus
(3) Query format
1 register = 2 bytes = 16-bit data
Field
ASCII mode
fixed character
string
Number of
characters
(Number of
bytes)
Remarks
Header ‘:’ 1
Slave address [H] Arbitrary 2 Axis number + 1 (01
H
to 10
H
)
00
H
when broadcast is specified
Function code [H] ‘1’, ‘0’ 2
Start address [H] Arbitrary 4 Refer to 6.7.2 (2), “Start address list.”
Number of registers [H] Arbitrary 4 Refer to 6.7.2 (2), “Start address list.”
Number of bytes [H] In accordance
with the above
registers
2 A value corresponding to twice the
number of registers specified above is
input.
Changed data 1 [H] 4 Refer to 6.7.2 (2), “Start address list.”
Changed data 2 [H] 4 Refer to 6.7.2 (2), “Start address list.”
Changed data 3 [H] 4 Refer to 6.7.2 (2), “Start address list.”
: :
Error check [H] LRC calculation
result
2
Trailer ‘CR’, ‘LF’ 2
Total number of bytes Up to 256
(4) Response format
If the change is successful, a response message that is effectively a copy of the query message,
except for the byte count and new data, will be returned.
Field
ASCII mode
fixed character
string
Number of
characters
(Number of
bytes)
Remarks
Header ‘:’ 1
Slave address [H] Arbitrary 2 Axis number + 1 (01
H
to 10
H
)
00
H
when broadcast is specified
Function code [H] ‘1’, ‘0’ 2
Start address [H] Arbitrary 4 Refer to 6.7.2 (2), “Start address list.”
Number of registers [H] Arbitrary 4 Refer to 6.7.2 (2), “Start address list.”
Error check [H] LRC calculation
result
2
Trailer ‘CR’, ‘LF’ 2
Total number of bytes Up to 256