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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 parameters one by one.
This is an example on the reading of the pressure unit code in the last result:
Master
Slave
—
Make a
Read N*words
request of 2 words at the
2307h
address.
On network:
01
03
23
07
00
02
7E
4E
01
Slave address
03
Function number (Read N*words)
23 07
D.A. address
00 02
Number of words to read
7E 4E
CRC
—
Answer to the request:
On network:
01
03
04
F8
2A
00
00
EA
9B
01
Slave address
03
Function number (Write N*words)
04
Number of read bytes
F8 2A
Word 1 & 2: read 00002AF8h
(Pressure unit code = 11000
→ bar)
00 00
EA 9B
CRC