Fuji Electric ALPHA5 Smart - Page 495

CHAPTER 13 RS-485 COMMUNICATIONS
Modbus RTU Communications 13-7
13
(3) Message examples
Monitor data: shows a message example to read out a feedback position.
<Query example>
Station No.
1 byte
01
･･･
When the amplifier station no. is "1".
FC 1 byte
03
10
Address 2 bytes
06
･･･
Specify
1006h
as the address of a
feedback position.
00
Information
No. of registers 2 bytes
02
･･･
Specify
0002h
as the number of data 1×2.
20
CRC check
16 bits
(2 bytes)
CA
<Response message example>
Station No. 1 byte
01
FC 1 byte
03
No. of data bytes 1 byte
04
･･･
1×4 =
04h
00
01
86
Information
Data 1 4 bytes
A0
･･･
000186A0h
= 100000 units
Data 1 will be FFFE7960h with -100000
units.
C9
CRC check
16 bits
(2 bytes)
EB
 FC 10h (Write of various data)
(1) Query from the master
Station No. 1 byte
FC 1 byte
･･･ 10h
(H)
･･･
Address 2 bytes
(L)
Specify the data address.
* For the addresses, refer to the table
13-1.
(H)
･･･
No. of
registers
2 bytes
(L)
Specify the number of sets of data n × 2
.
* Specify n × 10
on the positioning data.
* The max number of parameters and
positioning data is 9, and 45 for
others.
No. of
data bytes
1 byte
･･･
n × 4
* The positioning data are n × 20
.
(HH)
(HL)
(LH)
Data 1 4 bytes
(LL)
~ ~
(HH)
(HL)
(LH)
Information
Data n 4 bytes
(LL)
･･･
Write data for n sets from the specified
address
* The positioning data are 20 bytes per
data.
* For the data format, refer to the table
13-1.
(L)
CRC check
16 bits
(2 bytes)
(H)