Chapter 8 MODBUS Communications
Revision June 2010
8-9
11-bit character frame (For 8-bit character)
8N2
Start
bit
0
1
2
3
4
5
6
Stop
bit
8-data bits
11-bits character frame
Stop
bit
7
8E1
Start
bit
0
1
2
3
4
5
6
Stop
bit
8-data bits
11-bits character frame
7
Even
parity
8O1
Start
bit
0
1
2
3
4
5
6
Stop
bit
8-data bits
11-bits character frame
7
Odd
parity
Communication Protocol:
ASCII Mode:
STX
Start character’: ’ (3AH)
ADR
Communication address: 1-byte consists of 2 ASCII codes
CMD
Command code: 1-byte consists of 2 ASCII codes
DATA(n-1)
…….
DATA(0)
Contents of data: n word = n x 2-byte consists of n x 4 ASCII codes,
n
≤
12
LRC
Command code: 1-byte consists of 2 ASCII codes
End 1
End code 1: (0DH)(CR)
End 0
End code 0: (0AH)(LF)
RTU Mode:
STX
A silent interval of more than 10ms
ADR Communication
address:
1-byte
CMD Command
code:
1-byte
DATA(n-1)
…….
DATA(0)
Contents of data: n word = n x 2-byte, n
≤
12
CRC Command
code:
1-byte
End 1
A silent interval of more than 10ms
Summary of Contents for ASD-B2-0121-B
Page 1: ......
Page 13: ...Table of Contents xii Revision June 2010 This page intentionally left blank...
Page 17: ...Chapter 1 Unpacking Check and Model Explanation 1 4 Revision June 2010 ECMA Series Servo Motor...
Page 87: ...Chapter 4 Display and Operation 4 12 Revision June 2010 This page intentionally left blank...
Page 131: ...Chapter 6 Control Modes of Operation 6 22 Revision June 2010 Time Domain...
Page 267: ...Chapter 8 MODBUS Communications 8 18 Revision June 2010 This page intentionally left blank...
Page 271: ...Chapter 9 Maintenance and Inspection 9 4 Revision June 2010 This page intentionally left blank...
Page 291: ...Chapter 11 Specifications 11 8 Revision June 2010 11 3 Servo Motor Speed Torque Curves...
