M-system R7M-DAC16C, Instruction Manual

Page: 7 / 8

R7M-DAC16C
5-2-55, Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
Phone: +81(6)6659-8201 Fax: +81(6)6659-8510 E-mail: info@m-system.co.jp
EM-7803-AK Rev.4 P. 7 / 8
MODBUS FUNCTION CODES & SUPPORTED CODES
■
Data and Control Functions
CODE NAME
01 Read Coil Status Digital output from the slave (read/write)
02 Read Input Status Status of digital inputs to the slave (read only)
03 Read Holding Registers General purpose register within the slave (read/write)
04 Read Input Registers Collected data from the field by the slave (read only)
05 Force Single Coil Digital output from the slave (read/write)
06 Preset Single Register General purpose register within the slave (read/write)
08 Diagnostics
11 Fetch Comm. Event Counter Fetch a status word and an event counter
12 Fetch Comm. Event Log A status word, an event counter, a message count and a field of event bytes
15 Force Multiple Coils Digital output from the slave (read/write)
16 Preset Multiple Registers General purpose register within the slave (read/write)
17 Report Slave ID Slave type/ ‘RUN’ status
■
Exception Codes
CODE NAME
01 Illegal Function Function code is not allowable for the slave
02 Illegal Data Address Address is not available within the slave
03 Illegal Data Value Data is not valid for the function
■
Diagnostic Subfunctions
CODE NAME
00 Return Query Data Loop back test
MODBUS I/O ASSIGNMENT
ADDRESS DATA TYPE DATA
Coil (0X) 1 – 16 Digital Output (discrete output of the basic module)
17 – 32 Digital Output (discrete output of the extension module)
Inputs (1X) 1 – 16 Digital Input (discrete input of the basic module)
17 – 32 Digital Input (discrete input of the extension module)
33 – 48 Reserved (unused)
49 – 64 Module Status
65 – 80 Reserved (unused)
Input Registers (3X) 1 – 4 I Analog Input
5 – 16 ---- Reserved (unused)
17 – 24 F Analog Input
25 – 48 ---- Reserved (unused)
Holding Registers (4X) 1 – 2 I Analog Output
3 – 16 ---- Reserved (unused)
17 – 20 F Analog Output
21 – 48 ---- Reserved (unused)
I: Integer, -1500 – +11500 (-15 – +115%)
F: Floating
Note: DO NOT access addresses other than mentioned above. Such access may cause problems such as inadequate operation.