Mitsubishi Electric FR-E700EX Instruction Manual page 228

Communication operation and setting
(5) Message format types
The message formats corresponding to the function codes in Table 1 on page 225 will be explained.
 Read holding register data (H03 or 03)
Can read the description of 1) system environment variables, 2) real-time monitor, 3) faults history, and 4) drive unit
parameters assigned to the holding register area (refer to the register list (page 231))
8 bitsNormal response (Response message)
1) Slave Address
(8 bits)
1) Slave Address
(8 bits)
 Query message setting
Message
1) Slave Address
2) Function
3) Starting Address
4) No. of Points
 Description of normal response
Message
5) Byte Count
6) Data: Read data
Example: To read the register values of 41004 (Pr.4) to 41006 (Pr.6) from the slave address 17 (H11)
Query message
Slave
Address
H11
(8 bits)
Normal response (Response message)
Slave
Address
H11
(8 bits)
Read value (for frequency setting)
Register 41004(Pr.4): H1770 (60.00Hz)
Register 41005(Pr.5): H0BB8 (30.00Hz)
226
3) Starting
2) Function
Address
H03 H
(8 bits) (8 bits)
2) Function 5) Byte Count
H03
(8 bits)
(8 bits)
Address to which the message will be sent
Broadcast communication cannot be made (0 is invalid).
Set H03
Set the address at which holding register data read will be started.
Starting Address = Starting register address (decimal)-40001
For example, setting of the Starting Address 0001 reads the data of the holding
register 40002.
Number of holding registers from which data will be read
The number of registers from which data can be read is a maximum of 125.
The setting range is H02 to HFA (2 to 250).
Twice greater than the No. of Point specified at 4) is set.
The number of data specified at 4) is set. Data are read in order of Hi byte and Lo
byte, and set in order of Starting Address data, Starting Address + 1 data,
Starting Address + 2 data,
Function Starting Address
H03 H03
(8 bits) (8 bits)
Function Byte Count
H03 H06
(8 bits) (8 bits) (8 bits)
4) No. of Points
L H
(8 bits) (8 bits) (8 bits)
6) Data
H L
(8 bits) (8 bits)
Setting Description
Setting Description
HEB H00
(8 bits) (8 bits)
Data
H17 H70 H0B
(8 bits) (8 bits) (8 bits)
CRC Check
L L H
(8 bits) (8 bits)
CRC Check
... L
(n16 bits) (8 bits)
No. of Points
H03 H77
(8 bits) (8 bits)
HB8 H03 HE8 H2C
(8 bits) (8 bits) (8 bits)
H
(8 bits)
CRC Check
H2B
(8 bits)
CRC Check
HE6
(8 bits)