CHAPTER 13 RS-485 COMMUNICATIONS

<Response message example>

Station No.

1byte 01

FC

1byte 17

No. of data bytes 1byte 0C

00 ･･･ Feedback speed: 1000 [r/min] (3E8h)

Data 1

4byte

00

03

E8

00 ･･･ Effective torque: 80 [%] (50h)

Information

Data 2

4byte

00

00

50

00 ･･･ Motor current: 80 [%] (50h)

Data 3

4byte

00

00

50

CRC check

16 bits 19

(2 bytes) 5F

 FC 08h (Echo back maintenance )

(1) Query from the master

Station No.

FC

1 byte

1 byte

Information

Sub code

Data

2 bytes

2 bytes

CRC check

16 bits

(2 bytes)

･･･ 08h

(H) ･･･ Specify 0000h as the sub code of echo back.

(L)

(H) ･･･ Specify an arbitrary data.

(L)

(L)

(H)

(2) Response message from the amplifier

Station No.

FC

Information

Sub code

Data

CRC check

1 byte

1 byte

2 bytes

2 bytes

16 bits

(2 bytes)

･･･ 08h

(H) ･･･ 0000h

(L)

(H) ･･･ Echo back the specified data.

(L)

(L)

(H)

13

Modbus RTU Communications 13-15