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FG_F6_MODBUS_EN_01 / 2020-06-17
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Direct access
In Direct access, the master can only access to bits one by one.
Example for writing the state of the “Sequencing activation” bit (word 1, bit 14):
Master
Slave
—
Put in edition the program number on which the
functions bits have to be read
—
Make a
Write N*words
request of 1 word at the
6622h
address.
On network:
01
10
66
22
00
01
02
01
00
A7
44
01
Slave address
10
Function number (Write N*words)
66 22
D.A. address of the “Sequencing act.” bit
00 01
Number of words to write
02
Number of bytes to write
01 00
Word: write 0001h (Sequencing act. = 1)
A7 44
CRC
—
Answer to the request:
On network:
01
10
66
22
00
01
BF
4B
01
Slave address
10
Function number (Write N*words)
66 22
D.A. address of the “Sequencing act.” bit
00 01
Number of written words
BF 4B
CRC