Hitachi EH-150 Series, Руководство по применению

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Chapter 6 Communication Mode
6 - 45
Mod
b
u
s M
a
ster
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Function code 0x06 (Preset Single Register)
The function code 06 is a query to change state of the holding register of the slave. In broadcasting, the state of the
same holding registers of all slaves is changed.
(1) Sending data area format
Sending data area requires 4 words. Please set 6 bytes for head word.
Figure 6.43 Sending data area format (Function code 0x06)
1) Device No.: Set the slave number by hexadecimal number. (H01 to HFF. H00 is broadcast.)
2) Function code: Set the function code to H06.
3) Address of holding register: Set the address of holding register to change by hexadecimal number.
(H0000 to HFFFF)
4) Value of holding register: Set the value of holding register to change.
Ex.) Change the value of register 40255 of the slave No.51 to H54AC:
The head address of Sending data area WR100

WR100 = H0006
WR101 = H3306
WR102 = H00FE
WR103 = H54AC
(2) The state of receiving data area
1) Completed properly
When performance is properly, completion flag (t+1) will be ON, and nothing is stored in receiving data area. A
properly execution code is stored in a return code (s+0).
2) Receiving exception response
When an exception response is received, error flag (t+2) turns on, and the receiving data area is as follows.
Figure 6.44 Receiving data area format (Function code 0x06 / Exception response)
3) Other errors (except for exception response)
When there is no response from a slave or an abnormal factor is detected in the response, error flag (t+2) turns on,
an error code is stored in the return code area of the s parameter, and the number of receiving data is cleared to
H0000. (Data other than the number of receive data bytes maintains previous values.)
Please refer to section “6.3.5 Error detection in modbus master mode” for more information on error codes.
Exception code
Number of receive data (H0002)
H 8 6
Value of holding register
Device No. 0 6
Address of holding register
H 0 0 0 6
1 word
06: Function code
Address of holding register to change
Value of holding register to change