Shinko ACD-13A Use and care manual

1
COMMUNICATION INSTRUCTION MANUAL ACD-13A, ACR-13A (C5)
No. ACDR11CE1 2008.01
This manual contains instructions for communication functions of the ACD-13A, ACR-13A.
Serial communication and Console communication cannot be used together.
When performing Serial communication, remove the exclusive cable (CMB) from the USB port of the PC and
console connector of the ACD-13A, ACR-13A.
When performing Console communication, it is not required to remove the Serial communication cables.
However, do not send a command from the master side.
1. System configuration
RS-232C (C option)
(Fig. 1-1)
RS-485 Multi-drop connection communication (C5 option)
(Fig. 1-2)
2. Wiring
RS-232C (C option)
• D-sub 9-pin connector • D-sub 25-pin connector
(Fig. 2-1) (Fig. 2-2)
Comm. converter IF-400
RS-232C RS-485
No. 0 No. 1 No. 30
ACD-13A, ACR-13A
Host computer
Host computer
RS-232C
ACD-13A, ACR-13A
13 TX
14 RX
15 SG
1 GND
13 TX
14 RX
15 SG
Host computer Host computer
A
CD-13A, ACR-13A
A
CD-13A, ACR-13A
Shielded wire Shielded wire
FG

2
RXD
TXD
DCD
DTR
DSR
RTS
CTS
2
3
5
1
4
6
7
8
GND
RI 9
RS-232C RS-485
IF-400
CDM
FG FG
FG
FG
TXD
RXD
SG
FG
RTS
CTS
DSR
DTR
CD
2
3
7
1
4
5
6
20
8
RS-232C RS-485
IF-400
CDM
FG
FG
FG
RS-485 (C5 option)
When using communication converter IF-400
• D-sub 9-pin connector
(Fig. 2-3)
• D-sub 25-pin connector
(Fig. 2-4)
Shielded wire
Connect only one side of the shielded wire to the FG or GND terminal so that current cannot flow to the
shielded wire. If both sides of the shielded wire are connected to the FG or GND terminal, the circuit will be
closed between the shielded wire and the ground. As a result, current will run through the shielded wire and
this may cause noise.
Be sure to ground FG or GND terminal.
Recommended cable: OTSC-VB 2PX0.5SQ (made by Onamba Co., Ltd.) or equivalent (Use a twisted pair
cable.)
Terminator (Terminal resistor)
Communication converter IF-400 (sold separately) has a built-in terminator.
The terminator is mounted at the end of the wire when connecting a personal computer with multiple
peripheral devices. The terminator prevents signal reflection and disturbance.
Do not connect terminator with the communication line because each ACD/ACR-13A has built-in pull-up
and pull-down resistors instead of a terminator.
13 YA(-)
14 YB(+)
15 COM
1 GND
13 YA(-)
14 YB(+)
15 COM
1 GND
13 YA(-)
14 YB(+)
15 COM
1 GND
13 YA(-)
14 YB(+)
15 COM
1 GND
13 YA(-)
14 YB(+)
15 COM
1 GND
Shielded wire
4
3
1
6
4
3
1
6
Host computer
D-sub 9-pin connector
Host computer
D-sub 25-pin connector
ACD-13A, ACR-13A
13 YA(-)
14 YB(+)
15 COM
1 GND
ACD-13A, ACR-13A
Shielded wire
Shielded wire
Shielded wire
Shielded wire
Shielded
wire

3
3. Communication parameter setting
Set each communication parameter following the procedures below.
(1) Set the key 4 times in the PV/SV display mode.
The unit will enter the Engineering group.
(2) Press the
key once. The unit will proceed to the Input group.
(3) Press the
key several times until characters of the Communication group appear.
(4) Press the
key once.
The unit will proceed to the Communication protocol selection.
• To set each setting item, use the or key.
• If the key is pressed, the set value is registered, and the unit proceeds to the next setting item.
If the key is pressed at the SVTC bias setting, the unit proceeds to the Communication protocol
selection.
• Pressing the key reverts to the previous setting item.
• Pressing the key for 1sec reverts to the previous setting level (reverts from setting item to each group).
• If the key is pressed for 3sec in any setting mode, the unit reverts to the PV/SV display mode.
Character Name, Function, Setting range Default value
Communication protocol Shinko protocol
• Selects the communication protocol.
• : Shinko protocol
: Modbus ASCII mode
: Modbus RTU mode
Instrument number 0
• Sets the instrument number individually to each instrument when
communicating by connecting plural instruments in serial communication.
• Setting range: 0 to 95
Communication speed 9600bps
• Selects a communication speed equal to that of the host computer.
• : 9600bps
: 19200bps
: 38400bps
Data bit/Parity 7 bits/Even parity
• Selects data bit and parity.
• : 8 bits/No parity
: 7 bits/No parity
: 8 bits/Even parity
: 7 bits/Even parity
: 8 bits/Odd parity
: 7 bits/Odd parity
Stop bit 1
• Selects the stop bit.
• : 1
: 2
SVTC bias 0
• By connecting to Shinko programmable controllers [PC-900 and
PCD-33A with SVTC (Set value digital transmission) option], digital
set values via the SVTC command can be received from the
programmable controllers. See chapter “8“ on p.23.
• Control desired value (SV) adds SVTC bias value to the value
received by the SVTC command.
• Available only when Shinko protocol is selected during
communication protocol selection.
• Setting range: Converted value of 20% of the input span
DC voltage, current input: 20% of the scaling span (The placement
of the decimal point follows the selection.)

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4. Communication procedure
Communication starts with command transmission from the host computer (hereafter Master) and
ends with the response of the ACD/ACR-13A (hereafter Slave).
• Response with data
When the master sends the reading command, the slave
responds with the corresponding set value or current status.
• Acknowledgement
When the master sends the setting command, the slave
responds by sending the acknowledgement after the
processing is terminated.
• Negative acknowledgement
When the master sends a non-existent command or value
out of the setting range, the slave returns a negative
acknowledgement.
• No response
The slave will not respond to the master in the following cases:
• Global address (Shinko protocol) is set.
• Broadcast address (Modbus protocol) is set.
• Communication error (framing error, parity error)
• Checksum error (Shinko protocol), LRC discrepancy (Modbus ASCII
(Fig.4-1) mode), CRC-16 discrepancy (Modbus RTU mode)
Communication timing of the RS-485
Master side (Notice on programming)
Set the program so that the master can disconnect the transmitter from the communication line within a
1 character transmission period after sending the command in preparation for reception of the response
from the slave.
To avoid the collision of transmissions between the master and the slave, send the next command after
carefully checking that the master received the response.
Slave side
When the slave starts transmission through a communication line, the slave is arranged so as to provide an
idle status (mark status) transmission period of 1 or more characters before sending the response to ensure
synchronization on the receiving side.
The slave is arranged so as to disconnect the transmitter from the communication line within a 1 character
transmission period after sending the response.
5. Shinko protocol
5.1 Transmission mode
Shinko protocol is composed of ASCII.
Hexadecimal (0 to 9, A to F), which is divided into high order (4-bit) and low order (4-bit) out of 8-bit
binary data in command is transmitted as ASCII characters.
Data format Start bit : 1 bit
Data bit : 7 bits
Parity : Even
Stop bit : 1 bit
Error detection: Checksum
5.2 Command configuration
All commands are composed of ASCII.
The data (set value, decimal number) is represented with hexadecimal number.
The negative numbers are represented with 2's complement.
Numerals written below the command represent number of characters.
(1) Setting command
Header
(02H) Address
Sub
address
(20H)
Command
type (50H)
Data
item Data Checksum
Delimiter
(03H)
1 1 1 1 4 4 2 1
(2) Reading command
Header
(02H) Address
Sub
address
(20H)
Command
type (20H)
Data
item Checksum Delimiter
(03H)
1 1 1 1 4 2 1
Command
Data
Command
Acknowledgement
Command
Negative
acknowledgement
Command
No response
Master Slave

5
(3) Response with data
Header
(06H) Address
Sub
address
(20H)
Command
type (20H)
Data
item Data Checksum
Delimiter
(03H)
1 1 1 1 4 4 2 1
(4) Acknowledgement
Header
(06H) Address Checksum Delimiter
(03H)
1 1 2 1
(5) Negative acknowledgement
Header
(15H) Address Error
code Checksum Delimiter
(03H)
1 1 1 2 1
Header : Control code to represent the beginning of the command or the response.
ASCII codes are used.
Setting command, Reading command : STX (02H) fixed
Response with data, Acknowledgement : ACK (06H) fixed
Negative acknowledgement : NAK (15H) fixed
Instrument number (Address): Numbers by which the master discerns each slave.
Instrument number 0 to 94 and Global address 95.
ASCII codes (20H to 7FH) are used by adding 20H to instrument numbers 0 to 95
(00H to 5FH).
95 (7FH) is called Global address, which is used when the same command is sent
to all the slaves connected. However, the response is not returned.
Sub address : 20H fixed
Command type : Code to discern Setting command (50H) and Reading command (20H)
Data item : Data classification of the command object.
Composed of hexadecimal 4 digits, using ASCII.
(Refer to “7. Communication command table”.)
Data : The contents of data (set value) differs depending on the setting command.
Composed of hexadecimal 4 digits, using ASCII.
(Refer to “7. Communication command table”.)
Checksum : 2-character data to detect communication errors. (Refer to “5.3 Checksum calculation”.)
Delimiter : Control code to represent the end of command
ASCII code ETX (03H) fixed
Error code : Represents an error type with ASCII codes.
1 (31H)-----Non-existent command
2 (32H)-----Not used
3 (33H)-----Setting outside the setting range
4 (34H)-----Unsettable status (e.g. AT is performing)
5 (35H)-----During setting mode by keypad operation
5.3 Checksum calculation
Checksum is used to detect receiving errors in the command or data.
Set the program for the master side as well to calculate the checksum of the response data from the slaves
so that communication errors can be checked.
The ASCII code (hexadecimal) corresponding to the characters which range from the address to that before
the checksum is converted to binary notation, and the total value is calculated.
The lower 2-digit of the total value are converted to 2’s complements, and then to hexadecimal figures,
that is, ASCII code for the checksum.

6
Checksum calculation example
SV: 600 (0258H)
Address (instrument number): 0 (20H)
• 1’s complement: Reverse each binary bit. 0 will become 1 and vice versa.
• 2’s complement: Add 1 to 1’s complements.
5.4 Command example
(1) Reading (Address 1, PV)
• Reading command from the master
Header
(02H)
Address
(21H)
Sub
address
(20H)
Command
type
(20H)
Data item
[0A00H]
(30H 41H 30H 30H)
Checksum
(46H 44H)
Delimiter
(03H)
1 1 1 1 4 2 1
• A response from the slave in normal status [When PV=25 (0019H)]
Header
(06H)
Address
(21H)
Sub
address
(20H)
Command
type
(20H)
Data item
[0A00H]
(30H 41H 30H 30H)
Data
[0258H]
(30H 32H 35H 38H)
Checksum
(46H 46H)
Delimiter
(03H)
1 1 1 1 4 4 2 1
(2) Reading (Address 1, SV)
• Reading command from the master
Header
(02H)
Address
(21H)
Sub
address
(20H)
Command
type
(20H)
Data item
[0001H]
(30H 30H 30H 31H)
Checksum
(44H 45H)
Delimiter
(03H)
1 1 1 1 4 2 1
• A response from the slave in normal status [When SV=600 (0258H)]
Header
(06H)
Address
(21H)
Sub
address
(20H)
Command
type
(20H)
Data item
[0001H]
(30H 30H 38H 30H)
Data
[0258H]
(30H 32H 35H 38H)
Checksum
(30H 46H)
Delimiter
(03H)
1 1 1 1 4 4 2 1
(3) Setting (Address 1, SV) [when setting SV to 600 (0258H)]
• Setting command from the master
Header
(02H)
Address
(21H)
Sub
address
(20H)
Command
type
(50H)
Data item
[0001H]
(30H 30H 30H 31H)
Data
[0258H]
(30H 32H 35H 38H)
Checksum
(44H 46H)
Delimiter
(03H)
1 1 1 1 4 4 2 1
• A response from the slave in normal status
Header
(06H)
Address
(21H)
Checksum
(44H 46H)
Delimiter
(03H)
1 1 2 1
STX ETX
P00010258
02H 20H 20H 50H 30H 30H 30H 31H 30H 32H 35H 38H 03H
[Characters above are represented by ASCII]
Checksum
Checksum calculation range
[e.g.]
E
45H 30H
0
20H
20H
50H
30H
30H
30H
31H
30H
32H
35H
38H
0010 0000
0010 0000
0101 0000
0011 0000
0011 0000
0011 0000
0011 0001
0011 0000
0011 0010
0011 0101
0011 1000
+
10 0010 0000
[Hexadecimal] [Binary]
1101 1111
1
+
1110 0000
E0
45H 30H
[1's complement]
[2's complement]
[Hexadecimal]
[ASCII]
Checksum

7
6. Modbus protocol
6.1 Transmission mode
There are 2 transmission modes (ASCII and RTU) in Modbus protocol.
6.2 ASCII mode
Hexadecimal (0 to 9, A to F), which is divided into high order (4-bit) and low order (4-bit) out of 8-bit binary
data in command is transmitted as ASCII characters.
Data format Start bit : 1 bit
Data bit : 7 bits (8 bits) Selectable
Parity : Even (Odd, No parity) Selectable
Stop bit : 1 bit (2 bits) Selectable
Error detection : LRC (Longitudinal Redundancy Check)
Data interval : 1 second or less (Max.1sec of interval between characters)
(1) Message configuration
ASCII mode message is configured to start by Header [: (colon)(3AH)] and end by Delimiter [CR (carriage
return) (0DH) + LF (Line feed)(0AH)].
Header
(:)
Slave
address
Function
Code Data Error check
LRC
Delimiter
(CR)
Delimiter
(LF)
Slave address
Slave address is an individual instrument number on the slave side and is set within the range 0 to 95
(00H to 5FH).
The master identifies slaves by the slave address of the requested message.
The slave informs the master which slave is responding to the master by placing its own address in the
response message.
Slave address 0 (00H, broadcast address) can identify all the slaves connected. However slaves do not
respond.
Function code
The function code is the command code for the slave to undertake the following action types.
Function code Contents
03 (03H) Reading the set value and information from slaves
06 (06H) Setting to slaves
Function code is used to discern whether the response is normal (acknowledgement) or if any error (negative
acknowledgement) has occurred when the slave returns the response message to the master.
When acknowledgement is returned, the slave simply returns the original function code.
When negative acknowledgement is returned, the MSB of the original function code is set as 1 for the response.
For example, when the master sends request message setting 10H to the function code by mistake, slave
returns 90H by setting the MSB to 1, because the former is an illegal function.
For negative acknowledgement, the exception codes below are set to the data of the response message and
returned to the master in order to inform it of what kind of error has occurred.
Exception code Contents
1 (01H) Illegal function (Non-existent function)
2 (02H) Illegal data address (Non-existent data address)
3 (03H) Illegal data value (Value out of the setting range)
17 (11H) Shinko error code 4 (Unsettable status, e.g. AT is performing)
18 (12H) Shinko error code 5 (During setting mode by keypad operation)
Data
Data differs depending on the function code.
A request message from the master is composed of data item, number of data and setting data.
A response message from the slave is composed of a number of bytes, data and exception codes in negative
acknowledgements. The number of data to be dealt with in one message is “1”.
Therefore the number of data is fixed as (30H)(30H)(30H)(31H).
Effective range of data is -32768 to 32767 (8000H to 7FFFH).
Error check:2-character data to detect communication errors.
Refer to “(2) Error check of ASCII mode”. (p.8)

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(2) Error check of ASCII mode
After calculating LRC (Longitudinal Redundancy Check) from the slave address to the end of data,
the calculated 8-bit data is converted to two ASCII characters and are appended to the end of message.
How to calculate LRC
1
Create a message in RTU mode.
2
Add all the values from the slave address to the end of data. This is assumed as X.
3
Make a complement for X (bit reverse). This is assumed as X.
4
Add a value of 1 to X. This is assumed as X.
5
Set X as an LRC to the end of the message.
6
Convert the whole message to ASCII characters.
(3) Message example of ASCII mode
Numerals written below the command represent number of characters.
1
Reading (Slave address 1, PV)
• A request message from the master
The number of data means the data item to be read, and it is fixed as 1 (30H 30H 30H 31H).
Header
(3AH)
Slave
address
(30H 31H)
Function
code
(30H 33H)
Data item
[0A00H]
(30H 41H 30H 30H)
Number of data
[0001H]
(30H 30H 30H 31H)
Error check
LRC
(46H 31H)
Delimiter
CR+LF
(0DH 0AH)
1 2 2 4 4 2 2
• Response message from the slave in normal status [When PV=600 (0258H)]
The number of response byte means the number of byte of the data which has been read,
and it is fixed as 2 (30H 32H).
Header
(3AH)
Slave
address
(30H 31H)
Function
code
(30H 33H)
Number of
response byte
[02H]
(30H 32H)
Data
[0258H]
(30H 32H 35H 38H)
Error check
LRC
(41H 30H)
Delimiter
CR+LF
(0DH 0AH)
1 2 2 2 4 2 2
2
Reading (Slave address 1, SV)
• A request message from the master
The number of data means the data item to be read, and it is fixed as 1 (30H 30H 30H 31H).
Header
(3AH)
Slave
address
(30H 31H)
Function
code
(30H 33H)
Data item
[0001H]
(30H 30H 30H 31H)
Number of data
[0001H]
(30H 30H 30H 31H)
Error check
LRC
(46H 41H)
Delimiter
CR+LF
(0DH 0AH)
1 2 2 4 4 2 2
• Response message from the slave in normal status [When SV=600 (0258H)]
The number of response byte means the number of byte of the data which has been read,
and it is fixed as 2 (30H 32H).
Header
(3AH)
Slave
address
(30H 31H)
Function
code
(30H 33H)
Number of
response byte
[02H]
(30H 32H)
Data
[0258H]
(30H 32H 35H 38H)
Error check
LRC
(41H 30H)
Delimiter
CR+LF
(0DH 0AH)
1 2 2 2 4 2 2
• Response message from the slave in exception (error) status (When a data item has been mistaken)
The function code MSB is set to 1 for the response message in exception (error) status [83H (38H 33H)].
The exception code 02H (30H 32H: Non-existent data address) is returned (error).
Header
(3AH)
Slave
address
(30H 31H)
Function
code
(38H 33H)
Exception code
[02H]
(30H 32H)
Error check
LRC
(37H 41H)
Delimiter
CR+LF
(0DH 0AH)
1 2 2 2 2 2
3
Setting (Slave address 1, SV) [When setting SV to 600 (0258H)]
• A request message from the master
Header
(3AH)
Slave
address
(30H 31H)
Function
code
(30H 36H)
Data item
[0001H]
(30H 30H 30H 31H)
Data
[0258H]
(30H 32H 35H 38H)
Error check
LRC
(39H 45H)
Delimiter
CR+LF
(0DH 0AH)
1 2 2 4 4 2 2
• Response message from the slave in normal status
Header
(3AH)
Slave
address
(30H 31H)
Function
code
(30H 36H)
Data item
[0001H]
(30H 30H 30H 31H)
Data
[0258H]
(30H 32H 35H 38H)
Error check
LRC
(39H 45H)
Delimiter
CR+LF
(0DH 0AH)
1 2 2 4 4 2 2

9
• Response message from the slave in exception (error) status (When a value out of the setting range is set)
The function code MSB is set to 1 for the response message in exception (error) status [86H (38H 36H)].
The exception code 03H (30H 33H: Value out of the setting range) is returned (error).
Header
(3AH)
Slave
address
(30H 31H)
Function
code
(38H 36H)
Exception code
[03H]
(30H 33H)
Error check
LRC
(37H 36H)
Delimiter
CR+LF
(0DH 0AH)
1 2 2 2 2 2
6.3 RTU mode
8-bit binary data in command is transmitted as it is.
Data format Start bit : 1 bit
Data bit : 8 bits
Parity : No parity (Even, Odd) Selectable
Stop bit : 1 bit (2 bits) Selectable
Error detection : CRC-16 (Cyclic Redundancy Check)
Data interval : 3.5 character transmission times or less
To transmit continuously, an interval between characters which consist of one message, must
be within 3.5 character transmission times.
(1) Message configuration
RTU mode is configured to start after idle time is processed for more than 3.5 character transmissions
and end after idle time is processed for more than 3.5 character transmissions.
3.5 idle
characters
Slave
address
Function
Code Data Error check
CRC-16
3.5 idle
characters
Slave address
Slave address is an individual instrument number on the slave side, and is set within the range 0 to 95
(00H to 5FH).
The master identifies slaves by the slave address of the requested message.
The slave informs the master which slave is responding to the master by placing its own address
in the response message.
Slave address 0 (00H, broadcast address) can identify all the slaves connected. However slaves do not respond.
Function code
The function code is the command code for the slave to undertake the following action types.
Function code Contents
03 (03H) Reading the set value and information from slaves
06 (06H) Setting to slaves
Function code is used to discern whether the response is normal (acknowledgement) or if any error
(negative acknowledgement) has occurred when the slave returns the response message to the master.
When acknowledgement is returned, the slave simply returns the original function code.
When negative acknowledgement is returned, the MSB of the original function code is set as 1 for the response.
For example, when the master sends request message setting 10H to the function code by mistake, slave
returns 90H by setting the MSB to 1, because the former is an illegal function.
For negative acknowledgement, the exception codes below are set to the data of the response messages
and returned to the master in order to inform it of what kind of error has occurred.
Exception code Contents
1 (01H) Illegal function (Non-existent function)
2 (02H) Illegal data address (Non-existent data address)
3 (03H) Illegal data value (Value out of the setting range)
17 (11H) Shinko error code 4 (Unsettable status, e.g. AT is performing)
18 (12H) Shinko error code 5 (During setting mode by keypad operation)
Data
Data differs depending on the function code.
A request message from the master side is composed of data item, number of data and setting data.
A response message from the slave side is composed of a number of byte, data and exception codes
in negative acknowledgements.
The number of data to be dealt with in one message is “1”. Therefore the number of data is fixed as (0001H).
The number of response byte is (02H).
Effective range of data is –32768 to 32767 (8000H to 7FFFH).
Error check: 16 bit data to detect communication errors. Refer to “(2) Error check of RTU mode”. (p.10)

10
(2) Error check of RTU mode
After calculating CRC-16 (Cyclic Redundancy Check) from the slave address to the end of data, the
calculated 16-bit data is appended to the end of message in sequence from low order to high order.
How to calculate CRC
In the CRC system, the information is divided by the polynomial series. The remainder is added to the
end of the information and transmitted. The generation of polynomial series is as follows.
(Generation of polynomial series: X16 + X 15 + X 2 + 1)
1
Initialize the CRC-16 data (assumed as X) (FFFFH).
2
Calculate exclusive OR (XOR) with the 1st data and X. This is assumed as X.
3
Shift X one bit to the right. This is assumed as X.
4
When a carry is generated as a result of the shift, XOR is calculated by X of
3
and the fixed
value (A001H). This is assumed as X. If a carry is not generated, go to step
5
.
5
Repeat steps
3
and
4
until shifting 8 times.
6
XOR is calculated with the next data and X. This is assumed as X.
7
Repeat steps
3
to
5
.
8
Repeat steps
3
to
5
up to the last data.
9
Set X as CRC-16 to the end of message in sequence from low order to high order.
(3) Message example of RTU mode
Numerals written below the command represent number of characters.
1
Reading (Slave address 1, PV)
• A request message from the master
The number of data means the data item to be read, and it is fixed as 1 (0001H).
3.5 idle
characters
Slave
address
(01H)
Function
code
(03H)
Data item
(0A00H)
Number of data
(0001H)
Error check
CRC-16
(87D2H)
3.5 idle
characters
1 1 2 2 2
• Response message from the slave in normal status [When PV=600 (0258H)]
The number of response byte means the number of byte of the data which has been read,
and it is fixed as 2 (02H).
3.5 idle
characters
Slave
address
(01H)
Function
code
(03H)
Number of
response byte
(02H)
Data
(0258H)
Error check
CRC-16
(B8DEH)
3.5 idle
characters
1 1 1 2 2
2
Reading (Slave address 1, SV)
• A request message from the master
The number of data means the data item to be read, and it is fixed as 1 (0001H).
3.5 idle
characters
Slave
address
(01H)
Function
code
(03H)
Data item
(0001H)
Number of data
(0001H)
Error check
CRC-16
(D5CAH)
3.5 idle
characters
1 1 2 2 2
• Response message from the slave in normal status [When SV=600 (0258H)]
The number of response byte means the number of byte of the data which has been read, and it is fixed as 2 (02H).
3.5 idle
characters
Slave
address
(01H)
Function
code
(03H)
Number of
response byte
(02H)
Data
(0258H)
Error check
CRC-16
(B8DEH)
3.5 idle
characters
1 1 1 2 2
• Response message from the slave in exception (error) status (When data item is mistaken)
The function code MSB is set to 1 for the response message in exception (error) status (83H).
The exception code (02H: Non-existent data address) is returned (error).
3.5 idle
characters
Slave
address
(01H)
Function
code
(83H)
Exception code
(02H)
Error check
CRC-16
(C0F1H)
3.5 idle
characters
1 1 1 2
3
Setting (Slave address 1, SV) [When setting SV to 600 (0258H)]
• A request message from the master
3.5 idle
characters
Slave
address
(01H)
Function
code
(06H)
Data item
(0001H)
Data
(0258H)
Error check
CRC-16
(D890H)
3.5 idle
characters
1 1 2 2 2
• Response message from the slave in normal status
3.5 idle
characters
Slave
address
(01H)
Function
code
(06H)
Data item
(0001H)
Data
(0258H)
Error check
CRC-16
(D890H)
3.5 idle
characters
1 1 2 2 2